When you see how much people in the tech industry are earning in their 20's, or that there are some people that become millionaires / billionaires before their 30's, you start thinking differently about your future. Why wait until you're a senior citizen to do what you've always wanted? Working your ass off for 10-15 years and still able to do it, then retiring for the rest of your life to do the fun things sounds like an idea.

Okay, it's not for me either, but I wouldn't mind the ability to choose to work, instead of depend on it. Take some time off from time to time to work on private projects, take long vacations, that kinda thing.