Yeah but let's be honest - it doesn't feel like it at Disney. You might queue for an hour, but the in-queue easter eggs, interactivity, interesting things to look at (and in many - air conditioning) makes the time go quickly (or at the very least you overlook the loading platform and can watch others go on \ come off it and laugh at reactions).
Plus in many rides, because they're continuous load, the queue constantly moves, or moves in big jumps (eg: when they load the Mansion).
Contrast that to our local parks - where operations are horrendous and seem to aim for the slow-speed records, where guests aren't grouped until after the train is parked, where queues are hot, bare walls (or not much anyway), where the queue stays still for 5 minutes at a time... THAT makes it seem like a long queue, and therefore a long day.
You do feel tired after a day at Disney, but it really doesn't hit you until you are travelling back to your accommodation.
(i know you know this, i'm just spelling it out for those who don't see the difference.)