Well picking up my first NEW car( my Seaside blue Prius) in about 18 years this Friday. I'll take a train down to the city the dealer is in & the sales guy will pick me up there. I asked them .. even more suggested, it would be a very appreciated goodwill gesture if they would install my BT Chassis stiffening plate, Block Heater & Mudflaps. The sale guy said he check with his boss and ... NO, they won't install anything that they did sell.. "because they warranty everything they install and since they didn't sell it, they won't install it". I even offered to pay some moderate fee, but "no, they only instal what they sell". I wonder if I should have been more insistent or do you think it's a reasonable, if not very accomodating, position?
You are wrong. I have a Harley motorcycle. If Harley installs Harley parts it's OK and it doesn't void the warranty. Toyota is not responsible for non Toyota parts. It could be a sticky issue for them later. I once had a Buick & installed after market parts. When the trans failed they wouldn't fix it under warranty. I took it to arbitration and lost.
Congratulations on your new car. I'm sure you gonna love it! I know I'm loving mine and still find any reason I can to go for a drive! It still amazes me how much fun EV mode is!