There isn't a different counter for everything... dunno what Chinese you're thinking of (specifically I'm thinking Cantonese)... I know Korean has (I think) 3 different counters (or 2)...
For eg. you don't have to have different ways of saying a word like two with different ways such as "double" or "twice" or "second" etc. In Chinese I know there's only one other different way of saying "two", but that's the only number which changes.
To be slightly on topic: where does it say anywhere that the plural of platypus is platypi? It's like cactus.