Why would I as a company give random bounty hunters 'real' money? Instead, I'll pay them in tokens, that way they really have an incentive to make the project work. else they have zero value. There needs to be a good mix though, a good campaign is only as good as the tools it utilizes. If the marketing material is crappy, you can have a legion of twitter and facebook bounty hunters and it won't work. If you have professional material (paid for with e.g. fiat) but lack the means of deploying it, then it's also bad for your project.
And I think it's fair to pay the token of project's as a reward.