Tokens that account for Contribution Rights often involve human decisions. Token holders are usually entitled to a portion of token inflation, or a portion of network transaction fees, or in some cases, both.
Advantages: The token sale distributes tokens directly to users and the ICO builds the community at the same time. It is also the least likely to fail the Howey Test for a security in the United States.
Disadvantages: The barrier to entry is stiffer, risking less participation. Additionally, it could potentially centralize core network maintenance activities a in a small group of dedicated individuals.