Help ID comedy quote re musical theatre

Forgive me - it’s that vague.

Maybe Family Guy, maybe Summer Heights High, maybe something else altogether;
but someone somewhere has a hissy fit explaining the heirarchy of theatre.
Something like;
‘everyone knows its legitimate theatre; then ‘x’; then ‘y’; then ‘z’; then musical theatre’

Sorry for the nebulousness but I watched an episode of Glee tonight and it made me think ‘they want to be in musical theatre - don’t they know that comes below…ummm’

I am in the UK so it may be local, or not.

Thanks for any help as I am about to lose sleep over this.

Nos da.

MiM

I haven’t pinned down the episode, but it is definitely Stewie on Family Guy:

. . . or maybe Stewie’s teacher is the speaker.

Wow! Mimes are ranked that high…I never would have guessed.

It’s apparently from the 3rd season episode, “From Method to Madness,” if that helps.