No, it is not normal, and not expected of tenants.
BM this is misleading!
10 years and counting and it's been in every TA I've ever seen (mine and others).
I see it as an acceptable condition, especially if the curtains are brand new. I suppose if the curtains were old and gross I'd tell the LL to shove it, but to date have always moved into apts with nicely kept, cleaned curtains. I don't think it should be a big deal to leave them in the state you received them!