It's also interesting to remember they only get Males, at least from Craster. This may be their only way of growing in numbers. Have they been stealing babies from the wildlings all this time? Are there female Others?
Episode was interesting, they strayed a lot, I don't like that Jon knows about Bran. I guess the whole Craster's Keep stuff is interesting. But so now Jon goes out there, then comes back fights to defend the back of the wall, fights to defend the front of the wall?
I have a theory that perhaps Coldhands comes before Jon and the rest of the Nights Watch and saves Bran and the others, destroying everyone in Crasters, sending them fleeing. Leaving Jon and them to happen upon an empty destroyed Craster's Keep.