I appreciate the attempt but the reasoning of "it requires maintenance" is entirely moot. You have to do this regardless. Its just whether or not you publish it open-source. You are still saying, internally, this is good enough for customers, when you push it out.
This is a (very) thinly veiled attempt at a closed garden of sorts, IMHO. Its a "clean" excuse for not giving away the milk for free, but it falls short on actual reasoning.