Pre bowling is a gift, not a requirement. And the fact that a league actually lets you do so 2/3rds of the year is miraculous. I know of no league in our area that would allow this. YOu'd have to find another league that better suits your work schedule.
Since its a gift and a big one at that in your case, I don't see as you have any room for complaint about lane conditions. You should just be glad to be still involved in the league, IMO. By the way, does the league make sure they have a league official witness your pre bowling? If they don't they should.