How would you feel if the aluminum wiring loosened up(as it has an unfortunate tendency to do, which is why insurers shy away from it,) and it burned your house down- not only potentially harming your residents, their pets, and their belongings, but possibly spreading beyond that, as fires in California tend to do?

It was extremely aggravating and inconvenient, but I think in the long run, there was no harm done.

However, doing things like insulating the garage, adding a sunny window, some sheetrock and outlets would do no harm.

The flooring had a white paperish substance glued to it and the subfloor which had a black like coating on it. 

Also the economy of that location or state could be harmed and you would be harmed (even if you did really well in a downward spiraling market the market forces may overwhelm you advantages).Diversification is definitely a wise move to be safe. 

But I recommend not doing it because it could harm your property value now and in the future. 

Thus harming the prospective tenant.

Meaning, your free to be as self-harming, idiotic, financially damaging as one want's. 

Surges damage the internal electronic elements, but that won't be helped by ground connections.So there's no harm in an "awareness clause", but it isn't really related to the ungrounded outlets.

It seems like they are going way to far to protect people from possible harm.