I get 2's from the credit union kinda frequently. I have NEVER seen a torn corner, but have only heard it mentioned here before.
I haven't see them on newer $2's. I do see it plenty on older $2's. Especially red seal notes (US Notes). It's like everyone back then believed in witchcraft or something, lol.
Every single series 1928 $2 I've owned has had a torn corner, but it's less frequent on the '53, '63, and '76 notes.
$2 was the minimum bet at most horse tracks. Winnings would be multiples of the initial bet. So they were places that used lots of $2's, and $2's became associated with gambling, so much so they were often shunned in other places. Gamblers are a superstitious lot, and so they came up with many reasons to consider this or that $2 unlucky. The bad luck could be expiated by tearing off a corner of the note. A note with a missing corner advertised its bad luck, requiring a second corner to be torn off. So sometimes you'll find a $2 with all four corners gone.
Not a circulation or strap find, but a cool note I thought I'd share with some interesting numbers to me.
Here are some of my recent finds with red and blue ink. If ound another red two but do not have a picture.