I love games with or without plots. It doesn't bother me when there is no deep rich storyline.
Many of the old games didn't come with a plot or that the plot was shallow.
Come on Super Mario Bros. was very shallow in storyline department, just a plumber wanting to get the princess.
Even better, Pac-Man has absolutely no plot, yet it had an addictive flavor that keep people eating power pellets and evading ghost.
I understand when a game tries to make a good storyline and it has a shallow plot, but as long as a game has good gameplay I'm happy. I do understand also that it's just me that good games are really about the gameplay and the overwhelming feeling I get every time I save the princess, get in the top five on the high score, or that reach the end of the game. I think everyone lifts their standards too high for any game developer to get a perfect score, especially on the little things such as graphics, sound, and/or a storyline that is not rich.
(I only consider these things to be an additive flavor in a game that has great gameplay and replayability.)