Has anyone seen the movie "Jack Frost" with Michael Keaton? The basic story is described as a man breaks his promises and dies, but comes back as a WW--er, snowman, so that he can make amends with his son.
Maybe we're looking at this all wrong and it's simply a matter of epic daddy issues. That's actually not all that heretical....
If Craster was only doing what he was told to do (i.e., give his boys to the WW), how long did he intend to keep doing it? How many babies do the WW need? It's possible that some don't survive the transformation, so maybe he figured he'd give them as many as possible until he's told to stop.
Was there a plan in place for when he could no longer "perform" his role, or did he expect his daughter-wives to find someone to be the new Craster? Because if not, that's awfully short-sighted on both sides (Craster and his women and the WW). Granted, that assumes that we know what the WW are up to, which is presumptuous at this point. Maybe he or they thought they'd be rewarded with a second life or immortality of another sort, or at the very least, a prominent position in the new world order if he survived that long. After all, what was it in for any of them other than not to be killed by the WW? Seems like since they have what the WW want, they'd be in a better bargaining position.