I'm sorry, but someone on £100k/annum is highly unlikely to have any spare time to spend £30k on anything they like. To be earning that level of salary in the private sector, you will be at director level or equivalent, which huge amounts of responsibility and accountability, typically constant travelling away from home and excessive working hours, with absolutely no point to ever 'switch off' - it's 24/7 level of pressure, stress and responsibility. You won't be seeing your kids often. People work damn hard - past present and future - to get to that kind of salary and definitely wouldn't be posting on GAF right now like you and me. No company gives away £100k/annum to someone without expecting blood in return.
Now we can moan and say it's not fair and everyone should be taxed until they end up on the same salary, but then suddenly this level of responsibility becomes fruitless and the aspiration disappears. And by doing that we ultimately end up with a fucked economy down the line as the talent wanes.
All that aside, I think people wouldn't have an issue paying more tax as long as they knew they were going to get something to show for it. But as things stand, everyone is so cynical and sceptical based on the past.