For me, if I didn't work I'd have to find something to do. Work isn't just about earning enough money to pay the bills and have enough left over for a bit of fun - it's a big part of self-worth (at least for me).
I must say I do like my job a lot, and the busier I am the more I like it. This is just me though.
I have only ever quit a job once without having another one to go to. I was a door to door gas and telephone salesman in the summer of 1999. Walking around Glasgow tenements, walking the streets of places like Kilsyth, knocking doors from 11am and trying to convince people to switch their phone or energy supplier. It was terrible, soul destroying. I'd finish at about 9.30pm, home by 10.30pm, call the boss and take a bollocking for not making enough sales...and it was 11pm. 6 days a week unless I missed the targets, in which case I was back out on a Sunday. The day was gone. The week was gone. I was exhausted and after 4 weeks (of fantastic money, I have to admit), I quit. I was lucky enough that I had made enough money in those 4 weeks to see me through the summer before going back to uni.