I think the whole draw of Crossfit is really the community and the fact that they claim to be all-inclusive. Their exercises and "workout of the day (WOTD)" schedules are supposed to push you to do as much as you can do and to continue to strive for more, despite your current shape, size, age and/or fitness level.

But that said, there's a certain aspect to that commitment to improve your fitness level that borders on cult-ish and that's the portion that will probably lead people to over-straining themselves.

I personally don't believe in paying for exercise or gym memberships and the camaraderie of friends exercising together could be a huge motivation to get me moving. But that's just me.

At the end of the day, to each his own and no pain no gain right?

DISCLAIMER: I have friends who are in Crossfit Boxes and they think it's totally the bee knees. I myself am not one but I have pretty strongly formed opinions of the group which I hope doesn't offend.