Why is Disney not releasing Doug, X-Men, Spider-Man, and many others on DVD?

My guess is because those titles when released on VHS didn't rack in enough money to urge them to release them on DVD or maybe when they released the first few volumes DVD wise they didn't rack in much money (since that seems to be the reason behind why Gargoyles suffered the fate of not completeing all its seasons on DVD - only season 1 and part 1 of season 2 are out). Of course the problem is its pretty stupid that Disney don't make those titles avaliable business wise since they would still rack in money and whether the money be minimium or not it could help them make more movies and rack in more money. The problem is the wish to release DVD's when the series is still in high or mid high popularity but by time they do release most of us, customers or Disney fans, never know about them unless their Disney movies (notice how every Disney title commercial is a movie redone w/ special effects or brighter tones but never or very rarely a tv series commercial comes up). So technically the idea that Disney is evil is technically accurate (lol, how else are we supposed to find out about A tv series on DVD if once on a blue moon a commercial comes up for it and nearly every day a disney movie has a commercial for it).