There are a couple of Par 5's on my home course fronted by ponds. One of them you can get within about 86 yards of the center of the green before hitting the water. The other is about 92 yards.
The one with the water at 86 yards is quite a bit downhill with the pond at the bottom of the hill. Downhill enough that even from, say, 310 yards I have to hit 5-wood instead of 3-wood to be sure of not finding the hazard. On that hole I think the longest marked sprinkler is about 320-something but I could see big hitters wanting to know that layup distance even if they were 340, 350, 350 out.
So in a special situation like that I suppose 378 might be useful to a handful of players. A lot of good players would rather lay up to 95 yards if they could rather than playing too safe and laying back to 120 or something because they don't know their distance.