I personally check some ICO and that's result that's being before project finalised,Every project offered 50% bonuses and more but end of the day that's totally unexpected lose, also you are right all ICO are not scam,some ICO profit huge that's why people invested over here..
We have lost confidence in the ICO even though they offer 80% bonus, there is no profit and it makes ico fall.
In the end even though we get a bonus but the price does not reach the ICO price. this is the main reason why ICO dies slowly.