This is actually funny and disappointing, why will anyone want to hope on something they've not seen or something difficult like gambling, there's a difference between mere joke and faith like I believe your friend had so much faith to some extend he had to promise for celebration, this is surprising.
I believe most gamblers who sold out their properties for gambling had same faith as this, let's be realistic there's nothing like 100% accuracy or full confidence when placing a bet but people don't want to listen
No one can deny that they do not have this type of thoughts in their heads especially when they are damn sure of the game. When I have these sketchy plans of what to do with my gambling profits it is not buying something massive like as house, a car or business but to spend it on having a good time.
of course gamblers do have this thought but I can't express full confidence to such extend, gamblers really need to change this thought cause gambling can't be predicted fully so what will happen next if we never get to win the game we had high hopes on. Winning is fun and exciting especially gamble wins that come unexpected but it should not be taken for granted as we should maintain self control