It consumes a lot of power which could be piped off to Mexico and help useful cartel business.
Using LED lights, it’s actually pretty energy efficient.
At my biggest year, I had 36,000 lights in my yard. They weren’t LED lights. My electric bill matched my summer bill, so while it was expensive, it wasn’t outrageously expensive.
I haven’t converted to LED lights because they are just too expensive, and they don’t tend to survive long in the after-christmas sales. I did replace all my “SB” lights (which use .34 amps per 100 lights) with “ES” lights (which use .2 amps per 100 lights). I tended to pay between 50 cents and 1 dollar per 100 lights, so 36,000 lights cost me somewhere around 360 bucks.