I remember being taken once in another country to what was called a "peg" house, i.e. a brothel staffed with presumably desirable young men instead of women, males having "pegs" for sex instead of "pockets" like females, as it was explained to me. 

[from Mac (J. McRee Elrod)] 
The explanation I heard was that once upon a time the waiting boys sat upon a bench with pegs of graduated sizes inserted, projecting above and below the bench seat.  One selected a boy sitting on a peg the size of one's cock by looking at  the portion of the peg below the seat (the portion above the  seat being up the boy's bum). 

[from Steve Doonan] 
I heard the term Peg Boys some years ago, in reference to the Chinese crews that  laid track when the United States was building its transcontinental railroads. Certain of the Chinese men (so I was told) would function as "peg boys" to accommodate  the sexual drives of the other Chinese men. They would ready themselves for sexual intercourse by sitting on benches from which protruded pegs of wood, in various sizes  so that the men could become accustomed to the smaller sizes  first. I knew several men who went to a gay motorcycle "run" a few  years ago, as peg boys. At the wilderness site of the gathering, they erected a tent to which was tacked a sign,  "Peg Boys," and, when occupied, an "Open for Business." They "worked" in shifts throughout the day, to great demand. :-) 

[Mr. Shorts carries on:] 
Okay, guys, now we are getting somewhere. For various reasons, I did not mention the country in which I was taken to a "peg" house. It was in Mainland China, and although there were no peg benches shown to me there, they may have been elsewhere in the house. A young man was selected for me as I was a foreign person, and brought to me. Perhaps he had been chosen by peg size, as Steve mentions above. There was no talking between us as neither spoke the other's language. I had been informed he was a "Soochow beauty," a district of the country renowned for beautiful people, and that he was the pick of  the house. He was indeed breathtakingly handsome. I became  aroused the moment I saw him. He squatted over me, facing away, and by flexing muscles I never dreamed existed, got me off in a matter of seconds.  The man who took me there (also a foreigner) was a kind of know-it-all. Perhaps he did not know about the pegs and only told me that because he was the kind of person whose ego would not allow his saying, "I don't know."