If you’re like me, I’ll bet you get a whole bunch of robocalls every week. Some are scams, many are annoying political ads, and some are just hangups. These creeps often spoof numbers from your area to tempt you to pick up the phone. But when you pick up the phone, they hang up immediately. So what’s the point in calling you?

Guess what, they make money on those calls. Even if you don’t answer. How do they do it? They use caller ID, the very system that was intended to fight these kinds of calls.

When a number is displayed on a caller ID system, the phone company pays a small fee to the database that stores the number. The caller also receives a fraction of a cent in fees as well. But with multiple calls daily to the over 120 million households in the U.S. with landlines, those fractions of a cent can start to rack up.  One company estimates 5 billion robocalls were made to homes in just the first three months of 2018. So there’s a fortune to be made there.

Sometimes they’ll buy blocks of unused phone numbers and just keep calling them over and over. That racks up fees that your phone company must pay and will likely pass on to the consumer. So, even if they aren’t calling you, these crooks are still costing you money. While there’s nothing you can do to fight these crooks, phone companies are starting to wise up and cracking down on who they share these fees with.

And I know that many of you have signed up for the Do Not Call Registry. But that only works with legitimate companies who care if they’re annoying you and it doesn’t even apply to companies calling from overseas. The U.S. has no power to enforce these rules overseas.