However, the heating element in your dryer doesn't have to be run like that. You start the dryer, and it starts tumbling your clothers with the motor, and blowing some air with the fan, but the heating element can turn on and off in coordination with the rest of your house, and you wouldn't even notice.
Also, most of us run a load just before going to bed, and shuffle it to the dryer in the morning.
Do you care if the washer takes a little while before starting up while you're sleeping? I sure don't.