There are ways to increase coinholders. One of the popular few is the distribution of airdrops. These are literally free coins distributed to existing stakeholders if they qualify the requirements set by the management or by the Foundation. This is with the objective to create inspiration in working diligently in making the community stronger and powerful. Bottomline, adoption should be the end product of any rewards given to those who work. This is outside proof of work, although this is part of the smart contract wherein you get referral reward and chain referral reward every time the referral stake and vote (as a result has gained), the referee will get rewards.
Kudos to Blockstream for making this video to teach everyone how DDK rewards those who invited new investors and token holders. Mabuhay kayo! Atin ito, Filipino!