CNN Business  — 

After Kenneth Bloom retired from a career in the grocery business, he didn’t stray far. The 61-year-old focused on delivering groceries for Instacart, a role he’d been doing as a side-gig before retirement. The work gave him more flexibility, a source of income to supplement his pension, and the chance to continue indulging in his fondness for food shopping.

As the pandemic first hit the US, Bloom, who has now worked with Instacart for more than two years, was in the enviable position of seeing more opportunities to make money. But that didn’t last long. Several weeks into the health crisis, he started noticing that bigger ticket collections of orders, also known as batches, would get swooped up in the blink of an eye by one of the many other workers in Instacart’s rapidly growing fleet of shoppers.

“You have to constantly look at your phone because if you turn your head for a minute, that batch is gone,” Bloom said. While the risk of doing the job during a health crisis remained the same and there was no hazard pay, he started to notice a change in the orders he was able to secure: $7 to $10 batches in lieu of batches that could be many multiples higher in the first weeks of the pandemic.

As demand for grocery deliveries began spiking in March, Instacart announced plans to more than double its workforce of full-service shoppers, who, like Bloom, are treated as independent contractors. Several weeks later, Instacart announced it had already added 300,000 new workers and would add an additional 250,000 shoppers in select regions. The company also said it would begin instituting a wait list to prevent over-saturation. (Instacart said it currently has over 500,000 active shoppers and expects that number to fluctuate over time as the country reopens.)

Kenneth Bloom, an Instacart full-service shopper in Southern California.

While that surge in new shoppers offered the promise of a financial lifeline for thousands of workers during a sudden and severe economic downturn, some longtime shoppers felt sidelined. In interviews with CNN Business, some workers who predated the hiring spree expressed anxieties about how quickly batches would get snapped up — by real people or bots created to grab high-priced orders — and their ability to earn an income.

“Some time around the end of April, May, the batches weren’t as large monetarily,” said Carol Chantiny, who is based in Michigan and has worked as an Instacart shopper since 2017. “Something seemed to be going on.”

In response to questions from CNN Business, Instacart said there were more batches for shoppers to select from in the early weeks of the pandemic because of an imbalance between supply and demand. The platform had fewer than 200,000 shoppers at the time, and it was only able to deliver 50% of customer orders the same day or the next day. Demand from customers was up 500% compared to the year prior, the company said.

Instacart also said that from March to early June, it paused a system that prioritized which batches were surfaced to workers based on their shopper ratings. The company said the move was intended to insulate shoppers from being overly impacted by low customer ratings if they were unable to fulfill out-of-stock items like toilet paper. But as a result, it also meant there was no priority given to any shoppers, regardless of how long they’ve worked with the service, Instacart said.

“We’re incredibly grateful for each member of the shopper community and their commitment in helping bring families the household essentials they need,” an Instacart spokesperson said in a statement. The spokesperson also noted that the company has “introduced new recognition programs, product features, shopper perks, and resources to help make the shopper experience better tomorrow than it is today.”

Addressing the bots, Instacart sent shoppers an email in mid-July describing new authentication measures to verify shoppers and a ban on unauthorized third-parties from accepting batches.

Some shoppers told CNN Business they have seen a slight improvement in available batches this summer, but they attributed it to the fact that the job is not for everyone and speculated some new shoppers may have fallen off. They also said the rollercoaster is par for the course in working for the startup, which has been known to change how shoppers are compensated, including scrapping a “quality bonus” for 5-star ratings last fall. The last few months have forced some shoppers to rethink how much they lean on Instacart for their livelihoods.

Together, their experiences highlight some of the growing pains for Instacart and its sprawling fleet of shoppers. While the startup has emerged as one of the clear winners of the pandemic with a soaring valuation and hundreds of millions of dollars in additional venture capital, it has also been criticized over issues including its pay practices and inadequate worker protections.

One Florida shopper, who spoke to CNN Business on condition of anonymity for fear of retribution, said an internal “leaderboard” recently showed there were 900 active shoppers in their area, up from 400 less than a year ago. A Colorado shopper, who also spoke on condition of anonymity, confirmed a similar spike in their region based on the same information.

“When I would go to the bathroom I would take my phone with me,” the Florida shopper said. “You’re afraid you’re going to miss an order.”

The ability to pick up worthwhile batches became so difficult that the Florida shopper, who has worked for the company for nearly a year, has temporarily picked up a part-time job as an in-store shopper for a local grocer to make ends meet.

Others have come close to giving up on Instacart.

Daisy Cevallos, who is based in Southern California, and has worked for Instacart for nearly two years, said she’s largely stopped delivering for the service in recent months due to the low orders. “I couldn’t catch an order worth catching,” she said, adding that “out of desperation,” she searched for alternatives. She continues to deliver groceries for her own clients through an emerging startup called Dumpling, but hasn’t written off Instacart.

Among longtime shoppers who remain active on the platform, they worry both about their own livelihoods – with the hiring spree being just the latest reminder that Instacart can quickly fill jobs and edge out workers – and the overall quality of service on the platform from newer shoppers.

“There are a lot of people who don’t know the difference between a cucumber and a zucchini; between 2% milk and whole milk; between different kinds of apples – they think an apple’s an apple,” said Bloom. “You’ve gotta take care of the customer.”

Cevallos echoed the point. “They would shop the frozen first – a huge no-no. You’re going to deliver soupy ice cream,” she said.

Editor’s Note: W. Kamau Bell explores the growing gig economy on “United Shades of America” Sunday at 10 p.m. ET.