Somebody: It's pretty disappointing to see you give in to the traditional slippery slope argument. There are definitely some sophisticated philosophical critiques out there, but at the end of the day, a pleasure maximizing ethic is a more humane way of life than one which seeks to justify various forms of suffering as natural and excusable, because that's just the way things are.
Luckily, liberal capitalist society is willy-nilly guided by pleasure maximization via the profit motive, which in the long run will produce the same goals as a society guided by Benthamite philosopher kings. It'll just take longer to get there.