I wish these games get made often too..... But there are 2 reasons making a game like this hard to sell these days....
Designing 100 Levels by hand is harder than making a system which creates 10,000 different levels!! that's why a company will create more levels if they added rouge-like system to the game.
Most gamers these days want more replayablity, if they played all the 100 levels in a game that doesn't generate new levels...and mastered them.. know what? they won't play the game again (until long time passes if they really love it).
One solution is to create a game with both designed levels (for main mode), and generated levels (for endless mode).... But Designing a good level by hand is very tiring and expensive for the company... if they can generate 10,000 levels on the fly... why spend money on premade levels while games with only generated levels sell very well?!
RE: Hard Games: Is The Game Difficult or Unfair? How to make a Videogame more fair to players