I think Bitcoin price increase is not much affected to gambling. But now many people are stopped gambling and they are doing trading i think i am not sure but this is happening in market i think. According to me i am not playing much now i just play sport betting only that too if i am sure about my bet or else i will not play.
Off course it matters. Suppose you use to play with 0.01 (like I did) with the price almost doubled i've changed my habit to place 0.005 Bets. I am confident i am not the only one.
The same thing doesn't work vice versa, at least for me. When the price was 220 dollar, I was still making 0.01 BTC. not increasing, since I've learn to feel confident with
But like you say, the gambling behaviour seems to have changed, at least on bitcointalk. Where it used to be dice, now sports betting is the thing to do. Not wrong if you have some big events next to each other: Ronald Garros, Wimbledon, EURO 2016 and off course the Copa America.