At least you get the painkillers. Not sure what else they'd really do for non-emergent kidney stones anyway. Painkillers is probably the best you can hope for, and getting them quickly and sent home sounds like a great outcome to me.
Well, it's not instant in the US either. All ERs triage and kidney stones are low priority. I'm not sure how long is standard, but even if admission took less than an hour, you're still low in the MD's priority.
A friend just had them and he was in the hospital a few hrs while they IV flushed him with some chemical magic that supposedly helped dissolve them. I think the bill with insurance was 250.