The idea of a commercial space aping the design of a city is somewhat familiar when it comes to the suburban shopping mall. Malls were famously designed after urban downtowns or shopping districts. The big-box discount store, on the other hand—with its exposed steel ceiling, utter lack of ornamentation and warehouse atmosphere—makes no pretensions. So it is striking that even in such a utilitarian setting, and such a quintessentially suburban one, the old urban DNA still survives.
Greeters definitely are a thing here in Ontario Wal-Marts. And I'm pretty sure they're going to be doubled as anti-theft soon enough as well, if they're not already. Although they're usually super-old people doing it as of right now. I think they check receipts occasionally though.
Yeah, they're just "security" where I've lived. Just harass you if you walk out with a full cart or decide to opt for no bags.
I think they're gone in northeast American, but it's also possible I don't notice them because I rush through the store as fast as possible trying not to talk to anyone when I end up at Walmarts.