Growing up in Lancaster, PA, though the '80s, I remember some of what went on with pre-emptions and whatnot. I'm sure Aaron Sica can fill in some of my gaps.
Our TV Guide listed *four* CBS stations, even though only three markets were covered. Our Harrisburg/Lancater/Lebanon/York market had two CBS affils, and my local cable system carried both plus WCAU from Philly. So I always saw all the CBS shows in one way or another.
NBC was a different story...my very own WGAL (NBC Lancaster) must have pre-empted a good number of shows in the late '80s because I don't remember seeing them carrying $ale or Super Password. If they did, it was late night. KYW, then an NBC affiliate owned by Group W, would air games all over the place. I have vague memories of seeing SP airing at 3pm, and I don't think KYW had noon news, so they would air games in that slot as well.
My game show memory starts right about 1986 or 1987, so I don't remember what our ABC affils from Harrisburg (WHTM) and Philly (WPVI) carried in daytime games. I do remember watching Match Game for parts of its run on WHTM, though. I don't remember seeing Brucie or Double Talk though.
To go back to the topic posed here...I know from talking to Carol, the lady at WGAL who has made programming decisions there for the past 25+ years, that it's basically about ratings (money) and keeping us Lancastrians-who-hate-change satisfied, watching intently, and of course, buying whatever it is in they're trying to sell. They have rarely moved shows in mid-season in the past 20 years unless the show was cancelled.
WGAL did carry Caesar, Scattergories, and both versions of Scrabble through their entire run. I do not remember if they carried Wheel or not, but Goen Wheel did air here, and I have vivid memories of wondering "WTF!" about the $50 space. (Well, I was 8 or so, so the "F" probably meant "Fudge.") From growing up here, I always got the vibe that WGAL never really liked carrying games in daytime. I would occasionally see listings for WRC and be jealous. "Look what they've got!"
I remember going to my grandparents' house in northern PA over Christmas breaks. They live in McKean County, which is interestingly enough in the Buffalo, NY DMA. So WGRZ there aired a lot of shows I never saw anywhere else, including Classic Concentration and $ale. WGAL picked up CC right around the time they started rerunning the whole series, and kept it in daytime for what seemed like an awfully long time after.