Yes I agree with you on that. So, what was are you thinking of promoting the games then?
Marketing is the hardest part 
yes I know especially for indie games.
I think this is not true in the case of the indie games.
Indie game developers must make unique games, because they cant race with the big companies and big games.
Unique games has its own public and the web is a very good medium to reach these people.
And an indie game has low developing cost, so they dont need to sell many to get back the invested money or to reach the profit.
And as I know the indie/unique games has rising popularity. For example on Steam there is a category for indie games.
Endi, it’s true for any products. You can come up with the greatest game in the history, but if you don’t market it, you don’t sell it.
Unique doesn’t necessarily means fun. For example, I don’t play game because of their uniqueness, I play games because they are fun.The game can be a out of dead beat FPS genre, but if it’s fun for me, I will play it.
Games should have re-playability value, e.g. player should be able to play the game few times and find something new in it or just have fun every time he or she plays it.
I agree that one can have a niche market/audience and do well, it’s just harder to find a niche than appeal to masses.
Indie game should sell enough to get you through following development cycle. In other words you need to make enough money to live without worries for the following year if that is how long it takes to make second game.
Also it depends on the goal. If indie game dev is what you want to do for living, success is measured in sales. If you have a job and making games is a hobby, then success is measured by the release of the game.
Indie games gain popularity because they are not NFS 5 or Gears of War 3 or a game made based on a Hollywood movie. They are new IPs, new worlds. As I said earlier, the game can be in the dead beat genre, but if it’s something new, it will be interesting to play in. It doesn’t have to be unique 
And Steam doesn’t accept every single indie game. I know of the few examples that didn’t make it to Steam as those game were unique and didn’t appeal to Valve apparently.
To summarize, indie game dev is a business with a touch of artistry and should be treated with all the seriousness as business.
Exactly, for every successfull indie game, there are a thousand ones that just didn’t get marketed enough.