They ARE a thing in the US. Had them here for almost 2 years now. All they do is send an RF signal so no one has to physically see the meter. They just drive by and get the reading.
We got a visit from the utility co complete with police escort shortly after moving here because our usage is "4x the average household". Pointed out 3 adults, 1 child, 4 computers(2 of which draw more power than a grow room when gaming), 2 refrigerators, 2 huge tv's, xboxes, Hot water, laundry(remember the child), 3 window AC's, etc.
They never went further than the living room and haven't been back.
All they can tell is how much power your pulling and when. They have no idea what's using it.
I obviously have no way to know for sure, but I'm willing to bet anyone busted growing in the US due to electricity use, was likely already suspect and the cops went to the utility company for further evidence and an excuse. OR, it was a HUGE operation, or, they derped out when questioned about their usage.
Honestly, unless you're running a few 1k lights, I'd worry more about people seeing you carry supplies and what goes in your garbage than how much power you draw.