Usually they'll explain how who gets what percentage of the profit share. It's never really 50/50 though. I'd be careful of investing in dice sites as well because most of them run off with users funds at some point.
No it is not 50/50 how could it be you have only invested some bitcoin the dev has built and maintained it and built the traffic to the point where you decide to invest, be happy with around 10%.
I have a hard time working out what you are warning here what dice sites are you warning about running with users money please name at least 5 for your statement to have any baring?
I will name 5 that have not Bitdice.me, Primedice, Justdice, pocketrocket,Rollin.io and many many more that have not ran anywhere and they could have quite easily an made a fortune so don't aim that at 'most' of them because it is an untrue statement is it not?
I dont think he is warning about something, he is just asking the share of profits..