As I mentioned in another thread, Jeep and Chrysler cars in North America operate the high beams at FULL POWER as daytime running lights. Only the lights and the eyes of oncoming drivers get hot, especially when the weather is cloudy.
I agree with Panic Mode that most cars dim the low beams with PWM as daytime running lights and since they are dimmed then they last for a very long time.
My Chevrolet car used the turn signal lights as daytime running lights but I didn't notice if they were dimmed. I DID replace a burned out light bulb.
Some modern 25W resistors have an aluminum finned attachment.