There is the story Halagu rolled up the Caliph in a carpet or sack and had his men ride over him until death. To the Mongols this was a sign of respect as there was no blood spilled.
Plus, new rugs were widely available in Baghdad.
I do not believe that was a respect deal, as the Mongols had a thing about not spilling royal blood if I recall correctly. Which is strange considering how much blood they spilled overall, but I suppose us commoner blood don’t count.