When store rewards and membership cards first started, I was resistant. I thought it was not fair to get a discount just because I had the card. I thought that if the stores could afford to give the lower prices to some people, then they should just lower their prices and sell at that price to everyone. Well, I have learned that it is smarter to get the cards than to avoid them. I still really hate them for the reason mentioned, and I also hate how many I have to carry. They require a huge wallet and a separate case to hold them. My son is actually more annoyed than me because his wallet is bursting with cards from the pet store, movie theater, Subway, and more. It is also almost impossible to keep them organized. I will ALWAYS have the card out and with my payment method BEFORE I get into a store. I refuse to be embarassed at a checkout while searching for a card.
Now for the positive side of having these cards....they get you free things! I used my local convenient store "milk card" to get a free half-gallon of milk today. You get a free half-gallon after buying 5 gallons.
We go to only one restaurant when we go out. We earn points and after several visits we earn enough points to cover a free lunch for two! Most of the reward cards are free and you just have to have them scanned with your purchase to build rewards. There are cards for grocery stores that give you coupons.
I currently have over 20 membership/reward cards. The only one I pay for is Barnes and Noble. The $25/year is worth the savings per purchase I make.
If the stores or restaurants you use have a membership or rewards card, it is only a minor inconvenience to carry them for the rewards you get. If you want free things or discounts, they are a very easy way to get them!