They charge more for the amount of oil used.
It could be part of their scheme to get people in. They have a “quick lube” department and then their service department. Maybe their hope is that people bring their cars their for oil changes and get in the habit so they go their when something bigger needs done.
Frankly, the dealership has treated me right since I was 16. They also sell me parts at “jobber” cost.
Over the years I’ve become friends with the GM. Good dude. Well run dealership.
It happens, we have a good Toyota dealership here too. I wouldn't be asking too many questions if I was getting $30 oil changes there.

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my old hood when in Iowa, still decent area?
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