But $5 for a one time watch isn't too bad if you are only going to watch it once. Otherwise you buy it for $10-$15 and watch it once, and maaaybe come back to it later.
With kids movies on the other hand, kids tend to watch their movies more than once so the game changes a bit. $5 for 48 hrs vs 30 days vs $15 for perm access becomes a bit more complicated. I would feel bad for my parents if they had to pay for a TMNT movie each time I watched it :)