I have solved my Dropbox problem, at least temporarily, by encrypting my sensitive data and then putting it on a thumb/flash drive. For casual/everyday data, I'm using Google Drive.
Still, I remain confused, e.g., I thought one's Admin PW was
always required when installing or modifying files. That Apple allows DB (or anyone else) to do that is indeed a surprise. Or, did I allow that via a User Agreement that I did not throughly read, or is my Apple premise incorrect?
Curious and curiouser...