Safeway is sort of extreme. Many grocery chains do have some sort of loyalty card discount. But Safeway has huge discounts all over the place to the point where I make a point of slipping a loyalty card in my travel folder when I go somewhre that Safeways are common.
I refuse to shop at Safeway if I have any other choice. The Safeways I've seen display their discount as $1.00 off their (excessive) price, and then expect me to believe that I'm getting a discount instead of getting the real price that they artificially raised by $1? Feels pretty insulting and manipulative.
If you don't use a card at Safeway you are way overpaying. It isn't a "discount", the list price isn't competitive. But the phone number I give them is one that I had 20 years ago, so it's of limited use to them.