What's a "newsie"?

At the end of Chapter 12, "Merry-Go-Round," Sam Spade takes Wilmer Cook's two guns away from him while they are on the way to Caspar Gutman's suite in the Alexandria Hotel. Then in Chapter 13, "The Emperor's Gift," Spade gives the guns to Gutman as they enter and tells him:

"Here. You shouldn't let him run around with these. He'll get himself hurt. . . . A crippled newsie took them away from him, but I made him give them back."

Dashiell Hammett's novel The Maltese Falcon was first published in 1929. In those days newspapers were not sold out of machines as they are now. Many of the daily newspapers were sold on the sidewalks, especially at big intersections. Since papers sold for only five cents each, the men, usually called "newsies," had to work hard, often in fog, wind, and rain, to earn a living. They were typically men who were mentally or physically disabled. To embarrass and antagonize him, Spade is suggesting that Wilmer couldn't even cope with a physically disabled man who couldn't get any better work than selling newspapers for pennies at a time.
The other common ways of selling newspapers were in hotel lobbies, lobbies of office buildings, cigar stores, a few restaurants, ferry landings, and train stations. In all cases newspapers had to be bought from live persons. Some boys sold afternoon newspapers on busy streets after school let out. The Call-Bulletin, in which both Cairo and Spade saw the notices of the arrival of La Paloma, was an afternoon paper.