I enjoyed The New Scooby Doo Movies era too. (Not to be confused with the live action films.) It was fun to see the gang cross paths with other Hanna Barbera characters and celebrities of the day. (And Batman!)
How Casey Kasem kept sane during the Josie and The Pussycats crossover I have no idea. Shaggy and Alexander are pretty much two sides of the same cowardly coin.
Shaggy and Scoob aren't stoners, they just have a high metabolism. ;)