I am generally opposed to raising money through gambling, whether it is the use of lotteries by states or bingo by religious organizations. This is more a general distaste rather than a moral objection. I wouldn't veto such an approach, but I certainly wouldn't volunteer to help. I think that it is sad that Jewish communities can't support their synagogues without having to make profits from their neighbors' weakness. The law on this is very clear.
Contributions are only deductible on the amount over and above fair market value.
Come to think of it, in the case of scrip you shouldn't get a deduction at all, because you're not giving anything over and above fair market value. As far as I know, this principle is accepted by all movements of Judaism. I don't know the answers, but I'd like to see us think about the questions. I have notice a recent trend to highlight the actual tax deductable portion of various donations. The reason this is so successful is that it allows people to cheat on their taxes.