No, the Casino in Avalon has/had nothing to do with gambling. In the 30's it was the site for the Big Bands and an enormous dance floor. My dad as a young man worked for one of the Avalon hotels as a busboy one summer and met lots of big showbiz performers.
I myself grew up in SoCal and lived on a sailboat in my 20's in Marina del Rey (near Santa Monica). Seriously entertained being a tourbus driver in Avalon for one summer; the challenge of taking a large bus on the narrow twisty and steep road from Avalon to Two Harbors appealed to me and I almost took the offer.
My other avocation was flying. I flew from Santa Monica to Catalina Airport numerous times back then with friends in little rented Cessnas. It was great fun to sit out on the veranda in the sun, eating our Buffalo Burgers while watching some distant relatives (buffalo) grazing down the hill from us a hundred yards away. Just don't mingle with the herd, especially during mating season. Those critters are BIG and unfriendly.
Final note was that during Spring Break while going to grad school I sailed over to Avalon, tied up to one of the mooring buoys, and took the dinghy in to the pier. Walking in on the pier I saw a tall but thin guy who said "hi" as a walked by. I did a double-take and went back. It was a very emaciated John Wayne, who had taken his boat from Newport Beach over to Avalon also. I found out later that this was his last appearance in public. He hung around Avalon for only an hour or so, but felt lousy and told his crew to take him back home, and immediately checked into the hospital, where he remained for about two months before he died. Too bad he never played on a site that is recognized as the best gambling
site of our time.
Final final note: my mom and dad honeymooned in Avalon back in the late 40's. Now their hotel is a parking lot. Nonetheless, they celebrated their 40th anniversary by having their whole family stay in the Wrigley Mansion, the huge white home on a bluff overlooking the town. The Wrigleys, of chewing-gum fame and owners of the Chicago Cubs back then, brought the team to Avalon for spring training. But they eventually sold the mansion and it lived on for a while as a B&B. We loved the luxury of the place.
Lots of fond memories of Catalina. Haven't been back for amost 40 years.