I think because
1. He was the first X-man. He is Mr. X-man
2. He has been the x-men's primary leader since I could crawl
3. Until fairly recently, he has been the backbone of the team
4. In the movies, he has not been utilized. Movie 1 was Wolverine's movie, Movie 2, Cyclops was mind-jacked by the bad guys, and movie 3 he was killed pretty early on. First Class, well, no Cyclops
I don't know who is whining. As I said, I enjoyed the first two movies. I was happy and shocked to see this property come to film. I could not believe it. I went to the movies two or three times just to watch the first one. And the third one disturbed me. If I say we should see more Cyclops, I am not whining. It is because Cyclop is Mr. X-MAN, and has not been portrayed as the important chunk of X-men lore as he is.