For Paul Terry, he wanted for sure to grab the kids attention first...that way the parents would notice they're paying attention and they might be able to enjoy as well.
The cartoons still ran in theater, and whether or not it was for a kiddie matinee they were still part of the movie going experience of ANY movie (horror, drama, comedy). You'd get a trailer, a cartoon (or two), a short, and maybe a newsreel. That was the MAIN point of cartoons at the time in general.