Go fishing, read a book, go camping, climb Mt Everest, ride a bike, have a bar-b-que, play soccer, smoke a joint.....
Oh yeah, have sex....how did I forget that one?
In my 20's I did a stretch of unemployment. During which, short of climbing Mt.Everest (though I did climb as it happens), I did all the things you mention.
But I can't say it was the happiest time of my life.
I take your point - but there will always be ways to contribute to society (it will never be perfect), but possibly not in the ways we were once accustomed. There will always be ways to help - help will always be needed.
Hedonism isn't really fulfilling long term either - mores the pity.