I had a chance this week at work to talk to a couple of "old timers" that played poker, 21 etc. ( not professionally, the"VFW / Elks club/Home games of the time) .., in the 1940's and 50's but they shed some very interesting light when I asked them about "Poker" cards ..;
To them, they did not even know now the nuances of size, ... when buying decks, asking for or choosing a "poker" deck was never about a size, it was, ( "is" to them), a label meant to be sure to get a "normal" 52 card deck, vs. the very common & (
same size), Canasta, Pinochle , Euro and other similar packaged non standard decks sold wherever cards were sold ..
. They had stories of the occasional player that bought a new deck, only to find out after opening it, it was a Pinochle deck that could not be used to play poker, bridge or other "regular" games ... THiS makes a lot of sense, & may be the inital reason a deck was labeled "Poker".
It also makes sense that for the last 100 years or whatever, Professional casinos and poker players quickly preferred the slightly narrower Bridge size, for both ease of handling & dealing, which of course, has been the Casino standard for poker many decades ..
I doubt there has
ever been a price difference between sizes, there isn't now, ( the cost is in the color lithography, printing, packaging etc, not the 1/8" sides or if an extra joker is included or not), & as
@Old State mentioned, Casinos that historically spare no expense, give players free drinks, food, buy the finest chandeliers ect, would worry about the poker room decks.. & is also very counter intuitive to why they would always go thru "massive" amounts of wider Poker sized decks for Blackjack and other table games, where the players are actually closer to the cards.. ..
The more recent trend of seeing Poker "size" at some American Televised final tables probably has little to do with an extra 1/8" on each side of the card, & more to do with WPT/commercial paid endorsement deals for the casino to swap out their normal cards on the final table for the paid commercial endorsement Home game cards .. Bridge Jumbo would Televise the same as the massive index wides ..