I am starting to see the following.
These are done as door decals, sometimes on glass portions of the doors as you go into places. I follow the twenty foot rule about such places, usually try to be finished up within 20 feet of the door. That allows courtesy. Once I'm outside and the 20 foot away the people cannot say anything further to me. I'll vape like a fox.
Think it ought to remain the choice of businesses. Can understand a clean air policy for cigarettes. To be fair and examples we vapers should follow suit with smokers. It's about clean air, courtesy more than not. Even if we are cleaner, no point arguing it to any who choose not to understand.
If it becomes too much of an issue for a vaper. You can also make a choice like the businesses make a choice. You can choose to no longer do business with the business choosing to not understand. When people start being more selective of who they associate and do business with, i.e. they do not buy crappy junk from people who disrespect trans-sexual, blacks, Protestant, Republican or what have you, businesses will soon understand loss of money. That will motivate them to make better choices. We can starve out businesses. We're the commodity they cannot replace, consumers.
Don't like the
system 
the
system and create your own system. Not trying to sound selfish, self-absorbed. But when you see it every day and in every aspect of life, you can only fight hate with hate. And in the manner I'm choosing, I'm not fighting, I act peacefully. I want peace. I act peaceful, I expect peace. I do not prepare for war. I don't want war. I don't fight. I don't expect war. Eventually smacking hate around with itself like this will cause it to realize that it has lost. I and love win.
