The reason behind potential abusements on report badges is: If there is financial benefits with those badges, people might abuse it. They can create 100 account to spam, then use their main one to report all fake spams. In the second scenario, even real users might become report hunters, and might make their low quality reports. Some time people read fast, and don't care about general aspect of the forum.
I'm pretty sure that there are no plans for monetizing reports officially, and especially not with report badges. Yes, users could create unlimited accounts to generate fake reports, and contribute to the spam problem, but I very much doubt they would be willing to do that for just a reporting badge, especially when they could hop along into Bitcoin Discussion or the altcoin section, and report a mass amount of posts within a couple of minutes.
Generally, those that do report have very high percentages, and from my personal experience I haven't noticed too many users abusing the report function to benefit. Reporting badges are a good idea in my opinion because they encourage those that are already reporting to make more reports, but also rewards them without monetizing it.