Which is what I have been trying to get across.You are absolutely right.
A couple of things though. The single should be used to FILL an open tee time, or at least on open spot on a tee time of a twosome or a threesome, not to book a tee time as a single. That precludes a foursome from booking in that time slot, and if that entire time period is full (in say, the one hour window the foursome wants to tee off) then they will go somewhere else. Singles during busy times should only be used as fill spots, never as a tee time by themselves. A single should be able to get out pretty quickly, as there are always those groups who book as a foursome, but their fourth just isn't going to make it. That happens all the time. The single can always fill that spot.
Although, as I said earlier, they can always book as a single on GolfNow or the course website. But to expect to go out as a single because you don't want to be paired up with someone who MIGHT slow you down is ludicrous. In that case, find a time when no one else is out there and enjoy yourself.
If someone wants to go out as a single when there are open spots, I have no issue with them wanting to do so. Then, it's definitely better than sending out no one. But they should be walking on, not making a tee time.