When my car goes in..... there are "No Wash" notes all over the place....
If you do not want swirl marks all over your car, I suggest you do the same.
A dealer "courtesy" car wash is what it is.... judging from the paint of their loaner cars (which probably gets washed there all the time) I would stay away from it.
Current: 2016 F10 535i xDrive AW w/ Black Dakota, ZMM, ZCW, ZDA, ZDB, ZPP, 688 & Black Grills.
Retired: 2011 E92 M3 -AW
....ED April 29th, 2010
Retired: 2007 E92 335i -Space Gray.....ED Oct 19th, 2006