Personally we post our banking info, SIN number, etc. just in case someone may need it (of course for looking after our boat)
Now, seriously, we have posted our names, phone number, and email address on our boat for over 16 years now. I would like to be contacted should a marina employee, dock visitor, or dockmate notice something "unusual" with our boat, rather than come down to the marina one day to "find" an expensive problem myself, where earlier action could have saved me.
Maybe I am naive, but I don't see how someone having my name (not full legal name) and my phone number would be an "invasion of my privacy" or endanger us?
In the 16 years we have done this, we have never experienced a problem of any kind with this.