+1 on the tipping comment. Do the math assuming a 1% house edge on Craps and a 30% comp rate, and you need to get a $10 increase in rating for every $1.80 in hourly tips. If you make a single $5 bet "for the boys" per hour, then that needs to increase your rating by $25 to pay off. I'm assuming 60 rolls per hour here. Net-net, tip if you want to, but don't think that it will increase your rating enough to pay for itself.

As far as the Player's card, I can think of a great reason for sharing. Let's say that you live next to XYZ casino (not part of a national chain) and you head to that casino with a visiting relative. If you want to bump up your tier status quicker, you give your relative your card. They aren't planning to come back to that casino ever, so they have no chance for tier status on their own. Be aware that this is against the rules of some casinos, and this logic doesn't apply as much to Vegas casinos.