Possession w/ intent to sell a SCH IV CS?

A co-worker of mine was pulled this weekend after a crash and was charged with PWIMSD SCH IV CS. I know he is not a drug dealer, and had about 27 Xanax tablets in his possession for personal use, for which he was not prescribed. It seems harsh to charge him with PWI when the police have no evidence that he was doing so. Does anyone in the field of law know why he may have been charged this way? Because I know he was not selling them, he only purchased for personal use. It seems like it should be simple possession.