You talk about bounty campaigns, ICOs pay people with tokens in order to inform other people about the ICO. I'm a part now of DIW campaign and I will get tokens for this, but it doesn't mean I do this just for the tokens. People choose in which ICO will be apart, because if the ICO fail the tokens will have ZERO value. Therefor signature campaign is more than just a campaign than some people wear some ICO, is a vote of trust.