I'm not exactly sure I would call it laziness. At 1500 plates even at a 18 person party and a 33%~ish drop rate on
singles as we have now you are looking at roughly 500 fights average. Going by
pouch mobs it would be something more like a 5% drop with an average of 10 plates inside puts you at an average of roughly 170 fights. This is all assuming 18 player parties as well, if you are talking about 6-maning these fights then your looking at triple the rates, so 500~1500 fights.
As I said, I do not think laziness is exactly what I would call it, in a day and age when people did VW a lot and most people did not need plates, these trials still sucked, but they were more realistic because there was at very least some amount of supply, but today, when no one does VW really and the plate supply is near non-existent? 1500 plates is ludicrous.