Comment by literalAardvark

One thing I really appreciate about cruise control is that my foot can be floating above the brake at all times.

This cuts an entire second off of brake times in motorcycling, where it's just a quick hand move that you MUST do (well, 80% of it, the throttle release part) anyway because if you leave the throttle on you will wipe out, so I'd assume it cuts even more for a move like a large lateral move of a leg in a car.

Only issue is that you need to be careful with that foot to avoid keeping your brake lights on at all times.

Note that this might only apply to driving stick. I'm not sure if left foot on brakes is best practice in automatics.