never though of stillshaving's tip of photocopying cards to save space and weight.
Here you usually have to swipe membership cards, but an app is a great idea otherwise!There are apps for your smart phone that you can use for loyalty cards like Air Miles, Safeway Club Card, tec. This has helped me get rid of 4-5 cards from my wallet.
I use one called Stocard for Android and it works well.
"Discard" is so much more "wife-friendly" than "toss at strippers".
All my store affinity cards are kept in a business card holder in the car. I take them out as needed.