jeremy: "...of course, in the UK, the masses are comfortable enough."
That is the key point - and some are a bit more than comfortable, and content. In which case they really don't care that there are others who are substantially richer, that's just the way it is and it doesn't affect them. The extreme poverty that exists in this country is virtually invisible; the occasional documentary brings it into consciousness but that passes. A sort of "I'm alright Jack" attitude. Maybe not entirely fair, all we can ever deal with on a daily basis is what we have.
The super rich are frequently far more aware of pockets of poverty in society, feel quite passionately about it, and do quite a lot where they can to relieve it.
It's those in the middle who often live in a world where it doesn't touch them - out of sight, out of mind.