Please, please don't do this. We 100% never said we want you to engage. What we said is that engagement is a minor factor in payments because it's often correlated with quality. What you are talking about here is completely disconnected from quality. This tactic in large part relies on preying on people's sense of reciprocity. You (and anyone reading) should expect this type of growth hacking behavior to end up falling into the same category as a spammer.