Anything over 4-5 floors is acceptable i suppose. But there are people in the library i'm in who get in the lift to go down two floors (for which it is quicker to use the stairs, i checked).
I get annoyed at people who go 'up' the same distance, but i suppose at least that can be hard work for some lazy people.
I just get annoyed very easily when i'm in the library surrounded by students.
I can get annoyed at non-ridiculous things too!
Genocide for instance, what's all that about eh? Doesn't that just get your goat?