The danger of throwing around ideas is that they get easily stolen by others, turned into reality and passed around as if it was their idea. Since this is the internet, putting out your ideas will give others ideas about it and not everyone is honorable to include you.
totally agree with you. once you open, it cant be erase from internet. specially these days, lot of scammers try to stole money with fake ICOs. so if you tell your idea here, publicly, scammer will you it for scam project in next day. they just need a idea to release a token.
Even if they get your idea, i'm sure that everyone of you have different point of view in each ideas here. Their only problem is how would they make it real after taking the idea, they should have know the process on how it is going to run smoothly. Of course they will still need some advisory in every idea they gave to make it possible soon.