Consulting often means lots of travel time.
Even remote customers will usually want to meet face-to-face at some point, and requirement gathering is often best done on-site.
This becomes an issue when you want to settle down and grow your family.
I did both, and in my situation it seems that travel is a bigger issue.
Even with crazy startup hours, we could usually get at least one shared meal a day and you know... see each other. We could also workout together. Maybe get a hug while I'm talking to a customer on one hand and coding in the other. It adds up.
I think the idea is that, with consulting it will always be like that (vis-a-vis the travel issue), whereas a startup - if successful - will eventually result in a scenario where you can cash out, and kick back and relax. Or, if not "cash out" at least ease off on the crazy hours and what-not, and gradually transition into a "normal" business.
The assumption that startups get to that point, when most don't even come close, is (to me) more dangerous than "consulting is like selling crack."
Sure, I doubt most of us would disagree with that. Startups are risky... they're bloody f%!#kng risky... but if you succeed, you have a chance at being legitimately rich. To some people, that's a chance worth taking, to some people it isn't.
Me personally, I prefer the idea of trying to build a product company and work for the big exit, to the idea of being a consultant. But I'm not making any claim that either lifestyle is objectively better... clearly it's a personal choice.
My customers accept to work remotely, including for requirement gathering, and I asked precisely because I have a 3yo (I do agile, ruby, rails, etl, .net): I went on-site only 11 days since the beginning of the year.
I guess it's a matter of picking the right customers maybe; not everyone will work this way.
In my experience a startup requires much more from you than consulting. In a startup the team expects you to give 150%, when you are consulting you can pace yourself.
This becomes an issue when you want to settle down and grow your family.