In theory, the answer to the question is NO. The entry system for each park is semi-complex. When you use any pass, be it a 3 Day Hopper, of an AP, you must enter your Index and Middle finger into a scanner. Upon your first time through, information is incripted onto your pass, and stays there. (Supposedly, everyone's hand is different, and the equipment is sensitive enough to detect these small differences.) Then, each time you go back, when you swipe your card, you put the fingers in the slot, and it scans them to make sure the information on the card matches the information that was scanned from your finger. So in theory, you can't switch a card with someone else.
Now after all that BS, here's something that will throw it way off. One time, I got my pass mixed up with my fathers, but still entered through the system with no problem. Me being 6'3'', and 200 lbs, have much different fingers than my 5'7'' 180 lb dad. So this leads me to believe that the Hi-Tech mombo jumbo I gave to you in the last section is for schnicket!
So technically, and legally, you're not supposed to do this. BUT there's a chance it might work. I don't want to get the rinky dink Moral Mouse Police on me, so if you wish to try it, that's your call. I think the Hi Tech stuff might just be a bunch of crap. Or maybe I got in as a fluke. Who Knows?