This is how western democracies currently function, though it does not imply that the results are moral or even good.
>"Those people who would have to pay then could either take their wealth and attempt to leave with it (with all the consequences for both parties that might entail), or they can pay the share they are designated, and attempt to make more money with their wealth/connections/etc."
This statement basically says 'take it or leave it', which I suppose is fine, but does not mean that the state which implements high tax rates will achieve its desired results, and this does not speak to the morality of the average voter either.
You seem to ignore my point, which is that people who vote for higher tax rates and increased redistribution of wealth are not actually doing very much to solve any real problem. Voting to raise taxes on the rich demonstrates little personal responsibility, as the voter does not pay to solve the problem, and does not even try to convince others of their moral responsibilities.