Meaning the authors get paid the more they publish?
How? Per paper or career advancements-->> higher salary?
That has been a good incentive to date (I insist, this is maths and there are very few possibilities for cheating in my field, but of course there are instances), as I see it, because this way you incentivate academic professors to really do research (otherwise one can have a truly leisurely life in Spanish public universities once one gets tenure, without any repercussions).
Well, it is a permanent 120Eu per month (usually inflation adjusted, more or less), which considering that the tenured professor salary starts at like 1800Eu per month, is not so bad (at least it is some incentive). You can end up with 5 (or 6, if lucky) of these.
You see: the problem is not the incentive, but the salary itself.
(All the numbers above are more or less with taxes and Social Security already discounted).
Edit: never underestimate the power of saving and compound interest.