Well I do support a wealth tax.
My reasons are that I am keen on hard work, self-reliance and family values. In that respect I'm very much an old-fashioned right-winger.
Over the last two generations we have seen enormous asset inflation, which economists agree is set to continue. This doesn't reward hard work because getting richer due to asset inflation doesn't require any work. It doesn't encourage self-reliance because the value of assets (houses, shares etc) are created by a functioning society, therefore other people, furthermore, it sets up those who don't have wealth, to fail. And it doesn't reward family values because inequality in society, through the cost of housing, has put family life under enormous pressure: we see this in all manner of ways which society now treats as a virtue rather than a necessity.
While I am quite prepared to accept that some of the very rich owe their wealth in part to their hard work, it's utter arrogance and very un-self aware to believe that's the only cause. Every very rich person owes their wealth in part to one or more of the following things: good upbringing, a decent education, peaceful well-ordered surroundings, the ability to do business under the rule of law in an environment with properly maintained infrastructure, employees who work hard and well, and plain good luck.
I also believe in a cohesive, peaceful low-crime society constructed on the middle class, and governed by the most able, not the most wealthy. It is generally agreed that this is being destroyed by economics. The results will be bad for everyone, even the very rich who will hide behind their security gates as they do in unequal societies like South Africa or Brazil for example.
Someone mentioned 1 Timothy 6:10 above. Here is another Bible reference: Matthew 25:29: For everyone who has will be given more, till he has enough and to spare; and everyone who has nothing will forfeit even what he has. That's what's happening right now - except that unlike in the parable of the talents, those who have, have not earned their additional wealth.
The purpose of a wealth tax is to redistribute this entirely unearned wealth so that everyone gets a fair chance and everyone has the chance to do a fair day's work for a fair day's pay.
Now tell me, what's wrong with that?