Beware the Bat... Why so unloved by the execs? When will it return? The world may never know.
It could be something to do with, aside from the budget thing already stated, the lack of a major merchandising presence. Other than a Happy Meal promotion (where the
only character was Batman... not even a Pygg), one solitary older collector's action figure (not even a line of it's own. It was incorporated into an adult collector's general DC line), and an oddly timed release of Valentines, you just don't see specifically Beware the Batman Batman merchandise. Just general Justice League/comic book type stuff. I'd blame that on the fact his partner in the series is a woman. And having a female lead character in a boy's cartoon is really something you can only get away with if you're Teenage Mutant Ninja Turtles.
That was the main thing that killed Green Lantern TAS. The show undid the damage to the character the movie did, but because the movie merchandise hurt Wal*Mart so much that they wouldn't carry a GLTAS toy line, despite being something different entirely. Meanwhile, the Teen Titans Go line (from a different toy company than Mattel) actually sold
out in every TRU I've been in, and they're the only carrier. Plus, you have to admit, TTG is much more kid friendly.