Well, it is "clear" that he is alleging that he witnessed what he believed was a violation of the law by your throw/toss/loft/whatever. If the prosecutor feels the elements of the offense were not met, or he (or she) decides it is not worth the effort to pursue, then you will not be prosecuted. The probable cause necessary for a criminal charge or arrest can be a rather minimal sort of thing. One can make a perfectly lawful arrest and still have the case rejected by a prosecutor for reasons entirely unrelated to the legality of the arrest. On the whole, a great number of lesser offenses are NOT prosecuted simply because there are too few resources available.

I mentioned Miranda because many people seem to think it's a requirement. It's not. In fact, maybe one in ten arrests will result in Miranda being required to be read to someone. Some agencies (NYPD is - or was - one) require that Mirranda be read when you slap the cuffs on, but, this a procedural thing and a policy, not the law (and also why you see it on TV a lot). I worked in an agency where we read Miranda to everyone we arrested as a matter of course even when it was not required.

I have no idea whether this officer was being overly picky about the offense because he had an ax to grind with you, or, whether you possessed a sufficiently flippant attitude and demeanor that would lead to a reasonable conclusion that you tossed them in an attempt to hit him. It would seem a silly thing for an officer to risk his career over such a thing, but, I suppose there are a few idiots out there.