Aside from the general tone of this, that's not how taxes work.
You can only pay VAT on the 50% of your income that you keep (and that is presuming you spend all of it). So you have 50% * 75% = 37.5% of your income left to give to charity.
I also find it a bit interesting that you are OK (presumably) with giving away 63% of your income to the government, where you have hardly any say in how it is spent, but offended at the idea that you should give anything else away when you can choose where it goes.
I don't think he was OK with giving 63% of his income to the government. In addition, some part of that 63% is going to another form of charity: welfare. I can understand how someone, after seeing how a non-trivial part of their income is given away to local poor people, might not want to also give money to foreign poor people.
You can only pay VAT on the 50% of your income that you keep (and that is presuming you spend all of it). So you have 50% * 75% = 37.5% of your income left to give to charity.
I also find it a bit interesting that you are OK (presumably) with giving away 63% of your income to the government, where you have hardly any say in how it is spent, but offended at the idea that you should give anything else away when you can choose where it goes.