They're still used extensively in the US. I lived 25 years in Australia without a chequebook, but since moving to the US I've written scores of 'em.

Mostly, the problem is that the US still lacks a system for transferring money freely between bank accounts. If you want to send someone some money electronically you wind up paying fees at both ends.

(Also, some people use cheques just to be annoying, like the old women who write cheques to pay for their groceries at supermarkets.)