They are getting paid. Don't like it? Resign. Find another job. Don't like any? Open your own business.
OP is right. Union only makes sense for job that are inherently dangerous where union's primary job should be ensuring safety.
So paid overtime, vacation, parental and sick leave, and 40 hour work weeks are, in fact, shameless excesses that have made office work worse?
Capitalists have the same option. Don't like the union? Resign.