Pokemon Zero Sprites

[Alpha Six]

That's like saying it's a waste of time to sprite a boss character for ANY video game.
I mean, you're only going to see them once, right?

Besides, a lot of events in this game are going to be reoccurring; in other words, no, you won't see them once and never see them again. This isn't like the other Pokemon games; this one is going to be a solid storyline and there's going to be a ton of events where you'll see unique Pokemon a lot more often than just once.

As for "normal" trainers getting unique Pokemon, not EVERY trainer is going to have uniques. Trainers that have uniques are usually reoccurring, anyway.