This assumption comes up too often, but as Sean was saying, it's completely wrong.
Wide angles have been used with great results on probably all genres, it's a matter of choice. You say wide lenses are rarely used in serious films when actually comedy might be the genre where they are used the least!
The Harry Potter films got more serious towards the end and most shots were 21mm or even 18mm, and there's tons of other examples out there, it's a stylistic choice, not something imposed by the genre. Not all horror films look the same, not all action films look the same, not all comedies or dramas look the same... the genre has very little to do with which lenses you should use, the same way the lenses you use will not define a style alone.
And please... don't feed Mark.