I'm putting this in general discussion because it applies to both retail store owners (GTW) and restaurant owners (DO). But if the moderators think it belongs somewhere else, feel free to move it.
I'm indebted to @BlueBlack007 for giving me the idea.
First of all, it is possible for your Sim to live at a store or restaurant. You can place a bed, shower, and source of food on the same lot as the store. I usually have my Sims live upstairs, but you can put their living quarters anywhere on the lot. You lock the door to household only and pay bills on the telephone or computer. If your Sim doesn't have a job or go to school, you never have to go back to your "residential" lot again.
But as BlueBlack007 pointed out, that's a waste of space, and we don't have much space.
So -- what can you do with this empty lot?
You can turn it into a park. You can put gym equipment there. You can set up bookshelves and computers and think of it as a library. You can set up a bar, hire a mixologist, and send your sim there to wind down with a drink after a stressful day minding the store. It will still be a residential lot, though, so you won't have any company. If you have Get Together, you can make your residential lot the club hangout and call a club meeting when you go there. If you don't have Get Together, you can throw a goalless party there.
You can then make a little more space in your world by bull-dozing a gym or the library or a bar or nightclub.
If you play rotationally, you could turn your whole world into residential, retail, and restaurant lots. The only people who would show up at the gym or library or museum or bar would be the people that your Sim invited.
