STOP PRESS: Beanies cause deafness

So I get on the bus this morning, and am all primed to scan my Chicago Card like a responsible little patron. Imagine my surprise when, on assuming the usual card-scanning position, the card scanner was not there.

It was then that I realised exactly what the bus driver had been yelling at me since I climbed aboard his bus: CHICAGO CARDS ON THE LEFT

And indeed, when I looked around the corner of the bus to my left, I found the Chicago Card scanner.

So what had I been hearing him say instead? SHOPPING CARTS ON THE LEFT

Nope, it didn't make any sense to me at the time either. Stupid woollen beanie.