everyone is commitment phobic...those who seem to not be, also don't really commit. they just appear to!
when you commit to something, you're also making a decision to stand by that commitment. and you can't truly commit unless you've considered what it takes to stand by that commitment.
so if you commit "easily", you're not thinking it through. things may be smooth sailing for you, who knows. but if they aren't, you haven't already made the decision to plow through. and when you do, that's when you're truly committed to whatever decision you've made earlier.
i say that there is no such thing as commitment-phobic.