In the Bay Area at least, libraries are where people without computers go to access the Internet. The Internet is the easiest way to perform a lot of basic life tasks, like interacting with the government. People without computers these days are generally lower income, so it's true that there are more poor people in the library.

In some areas, it is definitely significant that libraries have bathrooms and shelter. But the Internet is always a big draw. With more and more of life moving online, libraries are providing an extremely valuable service by making Internet access freely available.

That doesn't match my experience. The libraries around Redwood City are high quality and filled with families.

In San Francisco, Portland, and certain places in Los Angeles, there is a significant number of homeless people who make use of the library. I don't begrudge them the access to books, internet, learning, and a quiet place, but there is a small contingent who are mentally ill and/or disruptive and cause problems for other patrons. Cf. “Why we can't have nice things”

This is most likely true of any large city, but I don't have any first-hand experience beyond those three cities.

Except for universities and affluent suburbs I would have to agree with the assessment. Why not? It's warm in the winter, cool in the summer, you won't be hassled to buy something and there is free internet access.

As much as we would like it to not be true, in the real world free services attract the lowest financial class of people. Libraries are awesome, and I spent a significant portion of my life in them, but as soon as I could afford to not use them, I quit going to them.

Depends if the "real world" is the US, Sweden or, for example, Bulgaria.

In the US, this might be the case. In Sweden, mostly you'll find kids, moms and people studying (depending on the city, if it has a university or not). A very small subset is there for computer access, but it's certainly not a majority.

In Bulgaria, no one seems to go to the library. They check your ID when you go in and it's not really a place to hang out.

Libraries aren't the same everywhere.

The libraries in my city just reflect the people in the community around them. In poorer areas, they are mostly poorer people, in the city centre there are mostly students and workers, in richer areas there are lots of middle class families and older folks.

Any library in an area with a significant homeless population.