I don't know of any evidence wherein it supports the idea that Walmart helps, or is neutral to, small business. Anyone who can remember what the town was like before a Walmart moved in and can compare that to what happened in the small business environment post Walmart. Will most likely speak of better times for local small business. No small business can survive when Walmart has it all, and much more, in one location, for a lower price.
In my opinion, Walmart definitely destroys small businesses all around America. It can be proven that since Walmart has been established, several smaller "Mom & Pop" shops all around the country have had to close down. It is often extremely difficult for these smaller shops to keep up with Walmart's corporate pricing.
Walmart absolutely destroys small businesses. People look for bargains and convenience without concern to what their actions may cause. Walmart is a company that refuses to be socially responsible and people do not realize that by using Walmart again and again they are allowing this problem to continue and allowing it to grow.
Walmart does not destroy small business. I think that Walmart is better for bulk buy, or specific type of shopping that can only be done at a larger mart, but I still prefer smaller grocery stores. I like the smaller stores because they are friendly, easy to move around, can be cheaper, and nearby.