I do fully admit i wouldnt know how to define which is which. To me it pretty much comes down to your operating place. Out of your home or on your property that is also your home, fine. Store with signs and lights and a open sign, to bad.
I guess why i consider them different is just like you said. On the corner with signs and hours of operation etc i have no reason not to walk in there because your whole layout invites the public in. Same thing between the difference of home and store. If i just walk into you home i could get shot and killed and maybe nothing would happen. You shoot me for just walking into your BUSINESS you have a lot of explaining to do and are probably going to jail for ever lol
The point is these differences already exist in ways so i think thats where to start.
I could just never support people discriminating in that fashion with a public business. If you are that mentally deranged and or ignorant simply dont open a public business why would you.