It sounds to me like simple avarice. If producing the first season on DVD isn't going to make you enough profit to justify releases of the subsequent seasons either WAIT for the demand to go up or RELEASE FEWER COPIES. It's not that difficult, Disney. You DON'T just refuse to release the second season because they didn't sale enough copies of the first.

Also, the fact that Gargoyles still airs on the family channel might have something to do with it. If you really want to sell the DVDs, take the show off the air for a while.