The library is a nice place to escape too when the weather changes from summer to fall. Sitting out in the cold is uncomfortable enough to make sketching painful no matter how interesting the subject, the scenery or the views.
One option is to look for something else such as drawing in the library. There is a fair chance that more or several non-suspecting readers will pose for you; that helps a lot, particularly when one is still learning to draw people.
I noticed that there seem to be as many patrons of the library that are staring at a laptop, tablet or cellphone as there are readers using the traditional books that my generation grew up with.
Anyways, no matter what is so fascinating for them as long as they sit still. However, this is wishful thinking; the hand holding the book moves over and is replaced by the other hand, the head turns, a leg that was stretched out is pulled back and so on.
My experience is mostly gained with drawing buildings, trees, boats, cars or similar stationary objects that either don’t move at all or that come and go, but leave enough time to record the essential features and fill in the voids based on memory or experience.
So what about trying to draw people that are walking? There is no time left between looking and drawing when the subject keeps on moving. Is it probable that sketchers draw the moving figures entirely from memory similar to a musician who plays a tune without looking at sheetmusic? Perhaps a combination of improvising and reciting?
I look at several blogs from sketchers that are proficient at drawing people in everyday settings, wondering how they can do this. It is going to take me the rest of the winter and probably many visits to the library or similar venues figuring this out and practicing to get a handle on this.