Given how 1-2 works, not surprised 8-2 (Glabados Ruins) works similarly. Never actually tested if it happens before—sounds like it saves maybe 25-30 seconds (huge for this game).
The only place I prioritize bomb spam in any% is 9-1: Winged Warriors due to the nature of the level. Sending all of them to SelfDestruct one leader usually kills around the same time as Kytes killing the other two, then they're all re-summoned at the start of the next phase. Anywhere else bombs get used, it's because they're the only worthwhile rank 1 yarhi, due to having acceptable attack / attack speed, flight, and niche use in SelfDestruct.
In All Missions, they're also "spammed" in Ordered Chaos, since a simple lure with Llyud allows for 10x Self Destructs on the opposing Soul Crystal at the start of the mission. I still have to go back and time whether it's faster to bring Wyverns or another flier as well, or if 10x Bomb is simply faster.