Yes, it is a fallacy, because in both cases it misrepresents the premise.
In the case of taxes, the actual premise is, "I think [set X/behavior Y/product Z] should be taxed", so generalizing it to "I think more taxes should be paid by somebody" misrepresents the premise.
In this case, the actual premise is, "I think this is something publicly-facing businesses should do", so generalizing it to "I think _every_entity_ should do this", again, misrepresents the premise.
As for the restroom access, and the inevitable consequences, is your issue with the provision of the service, or with being obliged to deal with the consequences for less than fair compensation?
I stated above I was for welfare and medical services
This doesn't mean every space open to the public - be it public property or private commerce open to the public, needs to burden themselves with solving the problems of homelessness and drug addiction
That's good, and a fair position, and I don't begrudge you for any of it.
What I replied to was the part where you then switched topics away from any of that, to an assertion that, for some unexplained reason, one of the posters here should invite strangers into their obviously-non-publicly-facing-home's bathroom. I just don't see the connection there.
They seem to be saying "you want private companies to pay this cost? Ok, would you pay it yourself?"
Which seems entirely a fair comparison, especially for smaller/family owned restaurants