If you go to the wiki list and read some of the back stories.... Begging. A lot of them just relied on handouts to eat. Not too different from regular homelessness.
Actually you can, even in the US, although it's limited to major international airports. The terminal smoking area is like a giant room with industrial ventilation and double "air lock" type doors
I think that's only available at a select few airports now. I saw one in Phoenix many years ago, but I've never seen one in Seattle SEATAC or any other major airports, possibly because I stopped looking for them. I used to pay extra to fly through Colorado instead of Phoenix because you could smoke in the airport bar in Colorado, while looking at a beautiful mountain backdrop. It was also just an all around better airport.