Even though I have a CC permit (which is intended to keep me, and my family vertical), I wouldn't be drawing and firing on people stealing it for any reason unless they were a threat towards my person (where I can say repeatedly that "I was in fear of my life" honestly to police.) The lawyer bills, defense attorneys, and bad press (Austin is very liberal... there would be picketers saying how the thieves were misguided and just deserved peoples' love) would be orders of magnitudes of what a replacement generator would cost. Plus, if it does get stolen, I pay my deductible, and it gets replaced, likely with the same generator Pianotuna has. Then, there is the issue of shot placement, crossfire in a residential area, and many other really bad things.
Oh... Texas thugs shoot back. Since they really don't care about things like gun regulations, there is a good chance they might be packing a lot more firepower.
I tend to make sure things are well secured, with defense in depth. Yes, a thief can get the generator, but they will be using an angle grinder on both handles, then having to make multiple cuts underneath the genset to get at the security cable threaded through there, not to mention the wheels.