This, as far as I can make out, is how Hogwarts breaks down:

Gryffindor – The Heroes!
Slytherin – Evil!
Hufflepuff – We Have A Stupid Name!
Ravenclaw – The Other One!

So, like, basically Hufflepuff and Ravenclaw are the “filler” houses, there to round things out so you don’t just have a spy vs spy situation, with only students in the dining room either sitting at Gryffindor table and studying hard and being good of heart and having glowing auras of noble .. uh .. true-ness, or sitting at the Slytherin table and twirling their moustaches and say “Bwaahahaha!” and strangling kittens.

But I suspect there must be more to Ravenclaw and Hufflepuff.

I think they have secrets, ancient and dark, unfathomable by the mind of man. Secrets best kept quiet. For ever.

That’s the only damn reason anyone would want to keep the house name “Hufflepuff” anyway, and not campaign and lobby constantly to change it to “Flamestrike” or “Hugeloins” or something.