If you make a great game, and it is truly great, it will sell.
Back in the day when these cliches were made, they went out on a limb.
Squaresoft was about to go bankrupt, and made an RPG, which were scarce at the time.
This RPG, working titled "Final Fantasy" because they weren't planning on making anything else, was a super hit, and now has 12 sequels and countless spin-offs.
A great man once said "Nothing is original anymore, everything is based off of something else. A great creator just combines the existing for something new."
Like your example "First-person shooter mixed with skateboard game," There have been (plenty) FPS games out there, and Tony hawk alone has churned out 9 skateboard games, at least. The creator of the cross over is doing exactly that, crossing the two genres.
Control, story, characters, etc. make the game a great one.
Yeah, the money invested in a commercial game makes LONG leaps unlikely, but there are still leaps done constantly.
Pikmin, mister mosquito, DDR, The DS, Boktai, all of the oddworld games, and many others are Leaps that have sold very well. Maybe not as first, but just as indie games get famous by word of mouth, they did. I personally laughed at boktai, when I saw it. But there a year later, I bought it.
So yeah, the list of commercial games has more clones on it than it should, but commercial games are not all cliche, as indie games are not all original. I have seen too many bomberman clones and tetris clones clogging websites. And very few indie games push the envelope. I think that website views are a indie's money. Chances are if they make a mario clone, people will play it and compare it to the original. But if they make a cooking/racing/rpg/dating sim, very few people will play it.
When it comes down to it, I think that a company will make clones first, and then the originals will come because they have cushion from their old games.





