The funny thing is that in many stores that have "loyalty programs", when I tell them I'm not signed up and am not interested in signing up, they'll just use a different loyalty card number instead (I assume it's the clerk's, but I'm not sure).
I don't know why grocery stores don't seem to care, whether it's corporate policy, or employee culture.
I don't. Personally, I don't care if they do this or not -- it's entirely irrelevant to me. I was just noting it out of amusement.
In general, I tend to avoid stores that have a loyalty program, because (as you note) their "loyalty card" prices tend to be the same as the normal prices at stores that don't.
"Thank you mister... Tester #2? You have $98,427 in savings this year".
Never worked again.