Need? maybe not, Want? maybe. I actually use mine occasionally. Both of my TV's are 110 volt and a DVR. Sometimes I don't need heat or AC, and simply want to watch something when not hooked up to shore power overnight. My hotspot also charges on 110 through a router, and I can run the fridge overnight on the batteries through the inverter and not use propane.
Really I could get by with out one, but I do like having it. If I add more solar I may upgrade to a pure sign wave one.