Thanks. I hadn't seen it.
"I steal his pants!"
I see that the Sage Advice website is not an official Wizard website.
They were making fun of Gamers and Stupid DM's that would allow stealing of pants. But we have to remember that back in the olden days, before Walmart, Pants where made of 2 parts
According to Michael Quinoin at World Wide Words, pants are a pair because, "before the days of modern tailoring, such garments, whether underwear or outerwear, were indeed made in two parts, one for each leg. The pieces were put on each leg separately and then wrapped and tied or belted at the waist (just like cowboys’ chaps). The plural usage persisted out of habit even after the garments had become physically one piece. However, a shirt was a single piece of cloth, so it was always singular."
so the Rogue would have to roll twice to steal the Pair of Pants