There are many reasons not to shop at Walmart but from a bicycle perspective the cheap bikes that come from department stores are often sloppily (or even dangerously) assembled and don’t do well on the playa. Make sure that your playa bike is built by a pro bike mechanic at a local bike shop.
A lot of good arguments exist to not to use Walmart for your burn supplies, the main one is that they seriously hurt communities by driving out locally owned small businesses. Please shop locally and support family owned small business! Thank you!