Is bounty programs impacting negatively or positively to the success of icos?
I can't say the impact is 100% big but i think the impact is positive to the success of ICOs. The thing is, the project owner/dev don't need to spend their money to the bounty, just offer the tokens 1-2% from the total tokens to bounty. So yeah bounty programs is useful and worth it.
That is one thing I do not like about bounty campaigns, they are paying real work that the bounty hunters do with tokens that have no value yet and that they are not sure are going to have any value in the future, this is why when I see an ico paying with BTC or with ETH at least I know that they have some real funds to promote their projects and not just tokens.