-More natural disaster risk exposure, as I live in earthquake country.

The reason is because of the inflationary nature of money.

House hacking by nature is comingling the asset with rental. 

For example adding an Amazon box, lighting, or something of that nature?

For investments that are relatively static and singular in nature - shares of a private placement for example - the services of a self-directed IRA custodian can be sufficient. 

Or else is it just the crazy SF Bay Area market with overvalued properties that naturally sell higher than the rental market can bare?

Does the site have access to electrical power, natural gas, town water or sewer?

I know people, by nature, resist change.

Unfortunately the vast majority of landlords do not screen very well and rarely understand human nature.

Now everybody and their mother's cat is doing it so we might want to look into storage and notes but also groom and nurture our network of private investors and such.We have lost touch with nature.