Yep. I always carry my 3ds around when going to/coming from work and I check it every day at home.
In my city the best place to get hits are the subway stations that interconnect different lines - there are only four of them in my city - as I need to pass through at least two of them every day (in the morning and in the evening), and they are always overcrowded so I always get a few hits.
Apart from that, there aren´t good spots for streetpass in my city. There´s a japanese district in downtown, it´s always full of people but most of them are tourists, not geeks or videogame fans.
Streetpass is pretty helpful in many games! In RPGs like shin megami tensei is a great way to recrute monsters, in Pokemon X/Y it allows me to get lots of caramels, and raise the level of my pokemon fast, in Animal Crossing I was able to complete several itens collections by buying them through streetpass visitors. Very helpful.
