The Greatest of Debates - "On line" v. "In line"

[SuaSponte]

I've lived in NYC for several years now, and I would believe that New Yorker's are generally bright people, except that they obstinately insist that, for ex., when you wait to get tickets, you wait "on line". Any fool can see there isn't a line on the ground "on" which you are standing, but instead that you are "in" a line of people.

Teeming Millions, help me bring the light of truth and grammer to the benighted residents of my adopted home.

V.