There is no snobbery about Dan Brown books, more a question of taste, I like you wasn't over fond of "The Davinci Code", but the others are fine. (preferred the film)
Lots of people like fact based books either History, Biographies, there are people who like facts & figures.
So just keep reading what you enjoy.
I would read anything or at least give it a try before passing judgement, some people will not. but true.