Hmm, there are many people in my contacts, but very few are ‘friends’ with whom I would share passwords. My own abode has two wifi networks, one which allows public internet access, and one which also allows access to my private wired lan network. That includes, for example, printer access, so it is a valued privilege.
When aquaintances visit, I freely disclose the password for the public internet. If they ask “what is this other SSID”, I simply explain that it must belong to one of the neighbours. Unless of course they are genuine trusted friends, with a genuine need for access, such as wanting to print a boarding pass. In that case, I slip them a printed copy of the Pass phrase, that I keep hidden under a vase on the mantlepiece.
Not sure how my own system could be improved upon?