What are the things you can do to increase the people in join avenue per day? I only get 3 people per day, so it took me 3 days to get to 8 shops.
Get all 8 badges, beat the E4, unlock other areas postgame, things like that will increase the number I believe. Also I believe the number increases as the level of your Join Avenue increases but I'm not sure on that.
Official Cresselia of B/W2 and X/Y Boards Official Deoxys of OR/AS Boards
Join Avenue was kinda useless to begin with anyway. Sure you get extra people from going to their Pokemon Global link dream world houses thats all you could do.
No. Any communication with someone else would cause them to visit your Join Avenue, assuming you haven't already had them open a shop. That includes the Global Link, trading/battling (local or Wi-Fi), direct communication, etc. You can still connect to someone locally, and they'll visit your Join Avenue.
You can get some rare items (including berries) if you recruit the right people and level everything up, set up a Nursery that can help greatly with egg hatching, use the salon and gym to help with stats, etc.
For more information: http://www.serebii.net/black2white2/joinavenue.shtml