Any harm in leaving the TT plugged in all the time??

I leave mine plugged in all the time. Electricity is much cheaper than running the fridge on propane plus I keep the TT at a reasonable temp in the Texas heat. I don't empty my pantry between trips and most foods keep better at lower temps.
Matter of fact, I just installed a 50 amp service in my garage for the TT and run the power cord under the garage door. Cost me about $40 in parts and an hour of my time.