Contractor charged for installing my own thermostat

This seems petty but I feel like I'm being nickel and dimed. Is it worth complaining about?

I'm building a new construction and the proposal says it includes a programmable thermostat. I asked if I could provide my own Nest thermostat instead, they said yes. Then I was charged $250 to install it. I did not know I would get charged for this. It requires no more additional work than installing a regular thermostat. I even scanned the QR code and set up the app by myself. I would have replaced the generic thermostat myself if I had known I would be charged.