The thing is that Green is still being built along with other areas. I remember in 2014's townhall meeting that this was really the first time there were so many corpies.
There are places for ice cream, other stores, etc. but just like in Red, you need to RP it. Fuller Med would not be the only clinic in central Red and WEC in Central Gold and you can RP something, but when it comes to coded healing, in game the 'well known' ones are the ones that come to mind and we go to.
There is Baskin Robbins, other places you can use, movies, food courts, don't forget the Lucky Dragons.
RPing it can work.
Gold has 8 locations off the top of my head. Nine if you include another where are you can't buy anything but you can still hang out there. ;) Ten if you include the Energy Museum and then 12 if the two parks.
Green has several areas. 4 off the top of my head though I'm combining a few in the food court. There's a poolside bench, archives library, Lucky Dragon, park.
Then there is Blue.
New areas are being created but there's no shortage of places to RP or buy things at.
Owning businesses can be done and if you have a character who would come up with that then it's something you can go for.