You can do this in Japan. Why shouldn't you be able to do this?
Regards you can't just ignore zoning laws because you feel like it.
One of the ways you can reduce cars is by zoning to allow greater density, which enables forms of transit which are more space-efficient than cars are. It's a chicken and egg problem, but people will be crying out for better cycle ways and trains and buses if housing becomes more dense.
Also, having commercial spread throughout residential areas reduces the amount of travel between areas, because you don't need to go far to get to the amenities you want.
What you mentioned is a very common thing in multiple countries - No one is afraid of random people coming into the neighborhood. (Neither do they all have guns to protect themselves).
This already happens in my country. It's a great way to support entrepreneurship and small businesses. I can't imagine how authoritarian the country must be to criminalize this. Are you living in North Korea or Cuba by any chance
Don't you see an issue of every single person decides to do this in your neighborhood, traffic being the first thing.
The other issue too, is most people are renting out apartments, and then Airbnbing them. Like, at that point it's not your property, you're just granted temporary permission to use it. Likewise, most condo boards don't want you to use your property as an Airbnb.