Because once you donate money, you have given it away, and it's gone. If you're expecting something in return you are trying to make a purchase, not a donation.
Punishment would involve having something further taken away. If they jailed people for donating, that would be punishment.
> Because once you donate money, you have given it away, and it's gone.
Presumably to the entity you intended to donate to, no? I would argue that determining where your money goes is a right.. If I intercepted all of your future charitable donations for my own purposes you would be understandably upset.
Ha ha, so easy to refute. Is it unethical for the government to stop me from say, donating to a terrorist organisation? It's still "charity", right? ;)
donation are purchases -- you are buying capital for the fund of your choice.
if it turned out a charity you donated to was funneling money somewhere, they would be effectively stealing from you, as the thing you were purchasing was never given.