My hybrid has never been without power. I keep it plugged in on a 20A circuit 365 days a year. I was told yesterday by a motorhome owner that it was not good to do it, although he did not give me any ...
I, too, think the only issue involves premature battery failure if your converter is not a 3 or 4 stage unit. I killed a battery that way, and since have added a battery cut-off switch (coupla bucks from the RV store) and when I'm thus parked, I'll cut off the battery and put it on a BatteryMinder, which keeps it safely charged and desulphated. The BatteryMinder was about $40, the most expensive part of the deal.
Other than that, enjoy your rig more and worry less.