Since I started bitcoin in 2015 there are already bitcoin gambling sites and today they are still existing. I'm just thinking if gambling is one of the factors in increasing the bitcoin's value.
Anything that increases the need to hold bitcoins, even on a temporary basis like getting some before paying for a service, will contribute to bitcoin's increase in value.
This value is the 'currency' value of bitcoin and the only sustainable value it can acquire. The speculative value of bitcoin (or as a savings vehicle) can only be sustained by demand coming from it's use as a currency.