True... but if you lost power today, you could be up and running in no time, (assuming you don't mind ripping the battery and alternator out of your car / truck for a few hours). Also, if you have the time, you could pick up the lawnmower on craigslist for a few bucks, a used alternator for cheap ($24.95 at Pick-A-Part in Chilliwack... I'm sure the cost would be close at any local autowrecker), and the remaining parts from Princess Auto.
In a perfect world power would never go out, (and we'd all have enough money for this hobby), but, in a pinch, this would do, (assuming you already have an inverter kicking around)
But you are right... it can be bought for close to the same price, (maybe even cheaper), for a better one... But it's one more tool in your toolbox that you can set up in a pinch if need be.
Robert