>>150218231
Dexter's Lab was way worse. They just introduce cool characters like Vicky the spider girl, Mandark's sister, Gwen and becky, but no one really matters besides Dexter's boring friend group who are just "other nerds" as their personality. You aren't expected to really care about Dexter, his family, or Mandark, just as zombie FOP didn't expect you to care beyond Timmy, Cosmo, Wanda, his parents, and Crocker.
Early FoP paid more respect to it's viewers time in comparison. The side characters for the first five or six seasons mattered. I don't think the first few seasons had any characters that were truly "one-shot". Even those random singing villains from the hyper-safety daycare Timmy got sent to had like 3-4 episodes and played a role in the musical movie. The camp is closed down, and they no longer play a role in the series at that point because they serve no purpose. But randomly removing other characters that had built up only to have no satisfying conclusion to their story (Timmy's friends, Mark, or any of his love interests really) was just poor showrunning on all sorts of levels.