I don't see any moral qualms with opting to pay the least amount of taxes you legally can for the same reason I don't see any moral victory in choosing to pay more than you're obligated.

When my accountant tells me to sign here and here to save myself a few thousands a year, I don't ask him "wouldn't these few thousand dollars benefit the general public?" I keep what I earned because I know that if the table's were turned, the state would never choose to give me more than I'm owed either.