Buying a good greeting card is like an art form. You have to find the right card for the right person. Do they like to laugh? Get one of those singing cards. Are they more sentimental? Any card with a softly illustrated bouquet of flowers should do it. Do you hate that person? Get them a really boring card. Don’t make it an exciting moment for them.
Just don’t be that person who picks up these gems. You don’t want to be that person whom no one really wants to associate themselves with. That’s just an embarrassing place to be.