I don't really believe in good luck charms as far as a superstition, but feel picking a 4 leaf clover or something like that as good luck is just a fun thing to do. For instance, I never miss a chance to wish on a shooting star.
I got a rabbits foot (fake of course) from someone long ago and Rocket finds it irrisistable! I don't think it's lucky though, just fun to watch Rocket toss it into the air and play with it!!!
I've seen 4 leaf clovers, so yeah I believe in them. But no I don't believe in good luck charms. I think some people are just lucky. Luck of the Irish and all that! Some people are unlucky. Some people (quoting Cal from Titanic here), "make their own luck".
I am a very lucky woman, but I do not carry any charms with me!