Gotta disagree with you, DH. I'm as ambivalent about religion as you are, but I do listen to Dave Ramsey, and the way they frame the tithe is not at all about "lending" the church your money. Rather, it's about GIVING BACK 10% of God's money. That is, the money is never yours to begin with - it's God's. By giving back 10% and only living on the remaining 90%, you're acknowedging that the only reason you have any money at all is by the grace of God.
Note that I think that's nonsense, but that's how the Christians reconcile the tithe with the whole "neither-a-borrower-nor-a-lender-be" philosophy.
Yeah, look into the etymology of the word "tithe" - it's a punishment. It has the same root as the Roman practice of slaughtering 1/10 of a legion to punish them for defeat.
In any case, my point is that if people want to give to their church, give back, or however they want to phrase it, that's really their own decision.