> "It's not exactly charitable if you're not actually sacrificing anything"
Tax-deductible doesn't mean that the money comes straight out of taxes, it means that you don't pay taxes on the donation. So you give $1.00 to get out of your marginal rate, something like $0.28 or $0.35, in taxes.
In order to eliminate your entire tax burden (per your libertarian comment), you would have to donate considerably more than you pay in taxes. You'd have to donate everything you made above the 0% tax bracket (getting down to a net income of about $15,700 for a married couple.) There are actually people who do it -- pacifists who refuse to pay taxes that could fund wars, for example [0]. But even then it's only possible if your income starts low enough.
Tax-deductible doesn't mean that the money comes straight out of taxes, it means that you don't pay taxes on the donation. So you give $1.00 to get out of your marginal rate, something like $0.28 or $0.35, in taxes.
In order to eliminate your entire tax burden (per your libertarian comment), you would have to donate considerably more than you pay in taxes. You'd have to donate everything you made above the 0% tax bracket (getting down to a net income of about $15,700 for a married couple.) There are actually people who do it -- pacifists who refuse to pay taxes that could fund wars, for example [0]. But even then it's only possible if your income starts low enough.
[0] http://www.nwtrcc.org/practical5.php