The only stores I shop at that do this are Walmart and Sam’s. There may be other stores that do it, but haven’t seen it in any other store in my area. I have to believe if it was necessary more stores would be doing it. I do understand shoplifting is a major problem- I just don’t think this is the right solution. I think it is a way for Walmart to save on hiring adequate security. The only security I see at my local Walmart is an old drunk that was fired from LEO years ago for being a drunk. I am pretty sure he would be worthless in a serious incident. If their own employees are an issue then they need to re-think their hiring practices.
Both Best Buy and Fry’s Electronics do it too. I’ve seen many others do it, usually around the holidays.
My daughter's friend works in a large 24 hour grocery store and people regularly fill up a cart and try to take off. At night when there's only a few working and 20 lanes to sneak through, security is difficult.