I thought that it will be something "normal" because that's true gambling is for fun and sometime as a coping mechanism, but betting in a funeral doesn't make any sense. I can't being fun or happy when I see someone's love has been passed away, even I don't know personally with the one who died, but I know how it feels.
Using gambling as a coping mechanism or as a way to distract yourself from reality can get you addicted to it, it's the same thing for those that get addicted to liquor, smoking and drugs they do it so as to derive pleasure and escape emotional discomfort, what most people don't realize is that doing this can actually give you dependency issues. It starts when your brain starts adapting to it, you will always feel like gambling even when you know you are not supposed to, at this point you don't care about winning or losing anymore, your only focus would be to satisfy the urge to gamble.
It's true you can get addicted, but it's not always happen.
I know someone who work on weekdays and then have a party on weekend for every week, does he's addicted? can't really say, but he enjoy his life by doing that.