For clarification, if you read my message in its entirety, you'll see that I don't tell people they shouldn't stay at WM; I merely state the reasons why I don't overnight there or at any other store parking lots. I have my opinions of store parking lots, based on observations and the reports of others; They happen to include my "magnet for druggies and dealers" opinion.
If we're on a freeway passing through the outskirts of some town, my wife will sometimes say "let's stay at that WM over there". I'll always remind her that we don't know the town, nor do we know if this is the undesirable part of town. We'll keep going and stay at a campground. It really isn't worth it to me to save the campground fee or avoid the inconvenience of detouring off the freeway if I'm not going to feel safe or be able to sleep. Unfortunately, some of the undesirables come out late at night, after I've settled in, so moving on wouldn't always be an option.
Some folks have previously misunderstood my position as being "anti-WalMart", but that's not true. I shop at WM when it's convenient and if they have what I need.
Others have their own opinions, which I respect.