I believe that investors of Polkadot ICO where the very lucky investors since the ICO was launched few years ago. How i wish that there's a bounty for this project but i found nothing except for their bug bounty that is far beyond my skills. With a project such this that is well funded and with so much hype, i can only hope less for them to offer bounties like i used to participate in this platform.
Some project doesnt want to have bounty for a reason that they don't want to experience mass selling for bounty payment. and thats the reason I guess why they don't considered to have one here. If you know you can make your project to be successful without the need of other promotion like bounties or ads you don't need to have it as long as you are confidence in your ability for developing the project I don't think you need it .