Movies don't count.
A single, confined 80 minute story is different from a season's worth of 20 minute stories. I could see a Scooby-Doo adventure show working, but then again that's what "Get a Clue" was, and... well, "Get a Clue" had nothing to do with Scooby, and any cartoon duo could easily replace them and the show would more or less be the same.
That said, check out "Scooby-Doo and the Reluctant Werewolf." They barely had enough plot for 30 minutes, and turned the rest into a Wacky Races...eh... I'm generously calling it an homage. And even then, the race is padded with repetition, specifically of Wacky Race style commentary puns. That gets tired after the 20th minute of the race, if not sooner. It's a good movie when it does stuff, but it could have been a simple 40 minute special.