Indeed it is probably a lease van, if not companies like Chubb would have to consider resale value as they would only keep them for three or so years.
Clearly the back window is glass otherwise the wiper wouldn't be there so one way vinyl or not doesn't really matter, the fact is when they come to sell the van on they can strip the vinyl and have a usable wiper on a saleable vehicle.
Why waste money and time removing the wiper ?