FTA is a lot different that satellite my friend, I have been doing this for over 20 years and never blew one up yet. But if it makes you feel safer please do unplug it..
LOL! FTA is exactly the same, because it is satellite! Receivers, switches, LNBs, dishes, etc., basically all the same. Check my signature and note some of the Star Choice/Shaw Direct dishes and LNBs that I use, including using my Shaw Direct subscription dish to receive the unencrypted odd wild feed on the Anik satellites (watched some curling feeds on there last month) through my FTA receivers.
Just because you haven't experienced any problems, doesn't mean it can't happen when you don't unplug the receiver. It can be very easy to cause a short. I shorted out a port on a DiSEqC switch when a coax connector came loose.
More to the point of Star Choice/Shaw Direct equipment, when we had the old style LNB with the 2 port 22KHz switch (which was mounted outside on the dish, whereas now the 22KHz switch is built into the LNB) I had water/ice get in under the coax connector and waterproof boot causing a short. Fortunately, it was a very robust 22KHz switch and didn't blow out, just a loss of channels which after drying out (at night, up on a ladder with a hair dryer!) worked again. Unfortunately, it happened again (this was before I was into FTA and wasn't more experienced to know what to do to protect it) and finally, one time caused a total loss of horizontal signals on one of the LNBs, therefore requiring a new LNB. So a short can, and does, happen, even with Star Choice/Shaw Direct equipment.
Plus, with your experience, you should know that someone not experienced with satellite receivers would not know that when the receiver is not unplugged that the coax still carries 12-18 volts, and it is very easy to make a connection on the connector to cause a short, especially at the LNB (and if it is the tuner that the OP posted about is the problem, it may have happened). Therefore, it is always best, whether experienced or not, to unplug the receiver.