Re: Telling prospective wi-fi customers they are open to hacking

You can warn them --- which is a good thing to do, recommended civic
behavior.

You can try and sell the services of security auditing and repair.

Do NOT attempt to do both at the same time, or at different times to
the same customer: the "friend, this place looks really flammable,
you need some insurance, just so happens I sell the stuff" approach
has gotten a bad name for some reason.

Approaching people and telling them they have computer security
vulnerabilities and offering to fix them is widely taken, both by
potential customers and the police they call, to be a style of
extortion.

-Bennett