Walmart can be not a great place to be a worker, I think that's all Rainey was saying. On the whole, Walmart treats its employees badly in some ways. I'll post a link and pull some quotes. That doesn't mean that you shouldn't help out the workers, of course! I'm pretty sure her statement was just pointing out that Walmart can be a crappy place to work, and wasn't criticizing you for doing something nice for the employees

https://en.wikipedia.org/wiki/Criticism_of_Walmart#Wages
"Other critics have noted that in 2001, the average wage for a Walmart Sales Clerk was $8.23 per hour, or $13,861 a year, while the federal poverty line for a family of three was $14,630.[49] Walmart founder Sam Walton once said, "I pay low wages. I can take advantage of that. We're going to be successful, but the basis is a very low-wage, low-benefit model of employment."[50] "
"In January 2004, The New York Times reported on an internal Walmart audit, conducted in July 2000, which examined one week's time-clock records for roughly 25,000 employees.[78] According to the Times, the audit, "pointed to extensive violations of child-labor laws and state regulations requiring time for breaks and meals," including 1,371 instances of minors working too late, during school hours, or for too many hours in a day.[78] There were 60,767 missed breaks and 15,705 lost meal times.[78] "
"In March 2008, Walmart sued a former Walmart employee, Deborah Shank, to recover the money it spent for her health care after she was brain-damaged, restricted to a wheelchair, and nursing home-bound after her minivan was hit by a truck. Walmart sued the former employee for $470,000 after she received a settlement from the accident, citing that company policy forbids employees from receiving coverage if they also win a settlement in a lawsuit.[108] After a wave of bad publicity, Walmart dropped its suit.[109] "