I forgot to mention I always unplug also. Point well made as a lightening stoke can still damage a machine just powered off. I have been burned a few times over the years. Always unplug for safety in my environment.
I had a bad lightening strike here last April. It hit a very nearby tree, ruptured our water line, unearthed our natural gas line, ruptured the city water main, cracked a basement wall, blew out a bedroom window, blew all of the circuit breakers in our house, wrecked our electric clothes dryer, all of the telephones, cable modem and router, etc., etc. My computer and Epson 7900 were plugged into a 1500 VA CyberPower Pure Sine Wave UPS, which was also destroyed, but the computer and printer were not damaged. I still keep everything plugged in, but not without a good, and properly grounded
, UPS. My network cable went through the same UPS, and if that had not been the case I'm convinced the computer and printer would have been damaged even though the power supply was protected. Basically, your system is unprotected if any connected cable from the outside world is unprotected. Each is a potential path for destructive electrical energy.
FWIW, I've had the printer for 4.5 years and turn it off at the control panel whenever I'm not using it.