Mass nouns and counts nouns. Does getting it wrong ever matter?
Solution 1:
I think you are correct in that if a noun is unambiguously mass or count then the qualifier doesn't matter, the meaning can be taken from the noun.
However compare: I ate too much fish vs. I ate too many fish.
If the noun is ambiguous in that way, then the meaning must be taken from the qualifier. So if you mistook "fish" for a term that was always mass or common, then you could produce an ambiguous statement.
(Inspired by Shinto's example)
Solution 2:
The classic example (which is probably an urban myth) is a foreign learner saying "I ate a chicken last night" when he meant "I ate some chicken last night". Mistaking chicken (the meat) for a countable noun makes it sound like he ate an entire bird.
Solution 3:
Some words have different meanings depending on count/ noncount usage. If you turn in "a paper", it means you have given the teacher an assignment, while simply having "some paper" means you have plain paper with nothing on it. I have two papers, means I have two assignments. I have two pieces of paper means I have two pages. I have a chicken means I have a bird, and I have some chicken means I have some bird meat.
Most words only have one meaning and usage, so confusing the two just sounds awkward rather than truly confusing like the paper and chicken examples.
Solution 4:
I was recently in a grocery store where the express lane was marked "10 Items or Fewer." I made a mental note that that was a classy chain, so in a marketing sense, getting it right made a difference.
Solution 5:
You can't enroll in Tattooing 101 because you have too many classes. You can't enroll in Tattooing 101 because you have too much class.
You cannot make too many glasses if you don't have much glass. You can make fewer glasses if you have less glass. You can only make a little glass if you only have a little glass.
My uncle has too much wood in his cabinet shop; there's not enough space left for a new planer. My uncle has too many woods in his cabinet shop; there's no need for him to stock zebra wood.
My sister doesn't like that radio station; she says it has too much blues. My sister doesn't like that wallpaper; she says it has too much blue. My sister doesn't like that wallpaper; she says it has too many blues.