Are you sure Maxwell created the tentacles? While he does suggest he created some of the critters in this world he didn't create them all, and Iwas under the impression that these ones were not made by him.
Well when maxwell examines things about the tentacles he is suprised that they have the ability to reproduce, and that he did not intend for that to even occur. Either he was completly oblivious to the fact that they could reproduce, which is unlikely, or he created them and their was some sort of fault.
Some other creations maxwell made do seem to have some kinks in them that maxwell did not anticipate, so it is safe to assume he created them. But if you find it to be speculation then by all means delete it, I don't mind!
I also realize this comment is 6 hours old. Sorry!
The only thing I've been able to find that suggests he is surprised is mentioned on the Big Tentacle page. The closest thing I can find actually from the game or the devs is simply that he says "Babies?" when you examine the small tentacles. It doesn't seem to carry any element of surprise to it. I just fear creating a wiki-ouroboros that feeds itself from itself.