Icos look for bounty hunters to promote their project through the power of social media.Sometimes, some of these hunters also double as ico investors. But it looks like bounty hunters understand ICOs project and are able to determine very good projects before they invest because of their experiences in different projects.
If the project is good and has a potential, yes. Bounty hunters do invest as well especially if they know that the project will be hit its success at the soonest.
I personally was an investor after I joined their signature campaign, why? Because the project was very interesting and I thought that I would make some money there.
But this does not happen all the time but this is rare because good project do not come every month or every couple of months.