My work, as in day job, usually consists of 3-4 hours working with 3-4 hours having lunch, chatting with colleagues, staring at the window, reading reddit/HN/LJ, doing some 'transparent' research on my startup. And that's when I'm working hard.

Working on my startup could easily drag me into a 8-10 hours race with only a few tea breaks.

If by addiction to money, you mean necessity for it to pay the bills, then this is true for most workers.

I suspect those of us electing to work upwards of 60 hrs/week at startups have other issues to work out beyond the allure of money.

I don't think it's fair to say it's an addiction to money. That may apply to some professions but a lot of people working 40 hours a week are just making enough money to get by.