Now that you mention the Hilton Brand Standard, the times I was asked to present the card may have mostly been during the few years I had dropped back to silver while in a job where I wasn't travelling much AND could have also been in Canada.

I can now only think of one time (Hampton SEA Airport, can't remember which one) since flipping back to Gold that I've been asked to show my card, and it was because they'd given my room to another guest with the same FI LASTNAME as me (luckily it wasn't a sellout situation)... this makes me wonder if, had they not caught it when I checked in, would this person's room been charged to my card had they themselves just agreed to leave it on the card on file? Probably!