I agree with Jude's comments. I, too, wonder about my qualifications on critiquing especially given the minimal posting of my own images. I could make commentary on every image I see but would that not cause the original poster to say, "What the hell does he know about this/that?"?
I once came across a cartoon from the New Yorker. In it you see a guy standing on a chair looking intently at a painting on the wall and there are 2 women in the foreground talking to each other. The caption read, "Him? Oh he's the Art Critic. He may not know Art but he knows what he doesn't like". Kind of speaks to the qualification of many Critics...and especially here at GG.
We do have a few (less than in earlier years) qualified people but the vast majority are those guys that epitomize the spirit of GG...photographers who do this for the enjoyment...enthusiasts not Pros. So often you are going to get platitudes..."Nice Picture"...which really are of little help for growth or, as you have noticed, viewing without commentary.
GG is like the vast number of photo sites...loads of lurkers, some members, few comments. It's just the nature of the internet.
Perhaps you can take solice in the fact that people here *are* looking at your images. Yes, the silence can be deafening but at least your images are not being passed over.
So don't despair and take what you get. At least you are posting unlike others (me included) who don't have anything new to put out there for CC.
"Beauty is more than skin deep"