It's pretty convenient (and facile) to demonize the super wealthy. It's common to do so. I have no particular affection for them either, but also no particular hatred. I actually know one such person quite well, she's my wife's closest friend. I've seen what she does for her community, in secret. I'm also aware she has personal troubles pretty much like we all do. Wealth can't buy your way out of those often as not.
At any rate, they have influence, should they choose to exert it. We can moan about it, but it won't change. We can moan about the Egg Lobby too if somehow we think that does something useful.
I've long though that career politicians thrive, not on money, but on power and recognition. (They get the money anyway.) Why would 70+ year olds who are reasonably well off still run for office? Hmmm. They don't need the money, they could be enjoying their later years, but they run for office anyway.
Maybe they feel they are doing a public service. Or more probably, they realize if they retire, they become near nothings in Life. The can't walk into a resturant and "be noticed". It's status. They're important. And sure, if they retire, some folks will point and say "She used to be SotH" or whatever. But most of their "importance" and stature will be reduced to "What's your handicap?".
My boss, one of the few good ones, told me this as he retired. He went from being "important" (in our small pond) to being just another wealthy golfer. He was fine with it.
So am I, I'm not as wealthy, but I'm OK ...