They're still commonly used to pay bills for stuff like rent, though it's less common now than say a decade ago. For things like electric bills the provider is typically big enough to automatically deduct from your account, but there aren't really commonly available systems to do stuff like that with a private landlord. If you're renting from a big company they may have an electronic rent payment system and it probably charges you a fee to use it.

I currently pay my rent via wire transfer, which is I guess better than a check because it's electronic but is also worse because there's a fee. When I first moved away from home for a job I had to pay rent with cashier's checks (which meant going to the bank and paying a fee first to get the check).