Yup I agreed with you too, it totally up to manufacturers to decide if it voids or not hence they reserved the rights. When I was surveying dashcam for my new car that is soon to be deliver next week, the seller kept telling me we don’t cut wire and just tap to the fuse for power so warranty confirm no void, yet I am still doubtful. Checking with service centre got me same respond that they reserve to rights to void.

End up now I don’t want to install any dash cam haha. Too bad my car manufacturer also no offer their own brand dashcam. 

With usb port then the wiring gonna be like hard to conceal right?