More than a dozen states that legalized marijuana have seen a spike in illegal marijuana grow operations that utilize massive amounts of electricity.

I don't know what a grow operation looks like, I'm betting charging my Electric Vehicle at home consumes more electricity than plant lights. That EV charging can pull 40 amps for upwards of 6 hours if the battery is dead flat when returning from a long trip. Seems like an easy way to mask a grow operation would be just to lower your EV charge (say to 20A or so) rate to stretch out the duration, then run the grow lights at the same schedule as the EV charging. There's no way to know from the electrical meter what is consuming the electricity.