They were also featured in stories during Batman Beyond 2.0 that had Terry in college. There's no rule that says they have to quit being criminals at a certain age. Why would ANY criminal still be tearing it up with a hero or two after the first few times they're arrested? I'm not trying to over analyze every aspect. Some things might not make sense. The kid with the skull face and jack o lantern shirt came back as well as a rival leader of the local Jokerz gang [there were something like 200 gangs of them across the globe under the leadership of the Joker King, Dana's crazy brother]. 

This is also our first actual taste of being a team in action, so a smaller threat was needed. If you want I'll bring the Red T's into this and then they can all just be random losers.

[img]https://vignette2.wikia.nocookie.net/dcanimated/images/d/de/Ts.png/revision/latest?cb=20100430100621[/img]

-00492