I actually edited a lot of this original post out as I cover a good chunk of the info herein in other posts above; there is one bit of information that should remain, however, on the off chance anyone wants to know:
I have found some tantalizing information about vaudeville in Scranton in particular: Scranton seems to have been part of "the Mishler circuit", a small chain of theaters founded by one Isaac Mishler of Lancaster, PA. Mishler moved to Altoona at the age of 20, in 1882; in 1894 he opened a vaudeville theater there. The following year he opened another theater in Johnston, PA, and in 1903 opened theaters in Greensburg, PA and Trenton, NJ. Ultimately he controlled 24 theaters in eastern PA along the main line of the Pennyslvania Railroad, from Lancaster through to Wilkes-Barre and Scranton. Altoona was his home of operations; this actually is the source of vaudeville jokes about faring well or poorly in Altoona.
One problem: after reading John Beck's copy of "If You Can Play Scranton," I STILL have not found out much about the elusive Mr. Mishner. The book, which is devoted to the performing arts in Scranton, did not mention him at all. However, it does mention that one theater passed through a few hands early in the stages of vaudeville before folding, and it was one Mr. Poli who finally opened a permanent vaudeville theater some years later. I'm just going to assume that Mr. Mishler was one of those unfortunates who failed in this early attempt, and since we're talking about stuff that happened in the 1880's, it's moot anyway.