My friend group is pretty economically diverse and also cost-conscious, and most of our social activities are free or nearly-free. We hang out in public parks, get together in each other's homes, and go hiking, camping, or to beaches. Optionally, you can put out some cheese and crackers and a cheap bottle of wine, and now you're all having a nice time together for $20.
I'm well-off these days, but I still enjoy doing free/cheap stuff, because I'm there to hang out with my friends, and they're the same friends whether we're sitting on a blanket in a park, or eating three michelin stars. I highly recommend suggesting free activities to your friends, if they're currently in the habit of going out to bars and restaurants and other $$$ activities. Just try it! Maybe you'll all like it.
Try that when you're working 3 part time jobs at 70 hrs/wk to make ends meet, because most cities in this country are horribly expensive (especially housing/rent/etc).
I can understand the time-poor argument made by another commenter, but otherwise you're right - there are loads of social options that are inexpensive. Have a couple of drinks while watching TV/movie/sport at home, meet up and go for a walk, cook together, meet at a pub for the lunch special, etc.
I'm well-off these days, but I still enjoy doing free/cheap stuff, because I'm there to hang out with my friends, and they're the same friends whether we're sitting on a blanket in a park, or eating three michelin stars. I highly recommend suggesting free activities to your friends, if they're currently in the habit of going out to bars and restaurants and other $$$ activities. Just try it! Maybe you'll all like it.