I called the dealership and they say they will charge $160 for mounting, balancing, and calibrating the tire pressure sensors.

I have only one set of wheels and this past winter I purchased and mounted winter tires at the dealership and was unaware of them doing anything to the tire pressure sensors. But I called them today about mounting my summers on and they mentioned this calibration thing. Have any of you guys experienced this, and is it necessary? I know a tire shop that does the mounting and balancing at a cheaper price. If anything, how much would just calibrating the sensors cost at the dealership?

The only thing I can think of is that the winter calibration would raise the minimum pressure value before the alarm goes off, and that the summer calibration would lower this value...

My wheels are stock OEM 18 inch, my summer tires: Michelin Pilot Sports OEM, winter tires Dunlop Wintersport M3's.

Any help is appreciated!