While your version sounds like he went beyond the scope of his duty or authority, I will say here in Indiana we're on duty 24/7 whether in our take home or not. Personally I have better things to do besides reaming someone for a infraction if that's what it was? I have seen violations and made mental notes, plant them today and reap them tomorrow but a tongue lashing was a bit much. If I had seen you showing them off and really wanted to inform you, I would have said "Hey bud, you know those are illegal and if and when you had said "No way" I would have then said they are, I should know and look it up as you later did as to say yourself some money and possible points. Here, we don't have vehicle inspections so pretty much anything goes however there are specifics on flashing lights in red/blue/white/amber and a few other colors. For example, you can have a red & blue light on your car or dash and drive with it but its not illegal until you light it up. Now go figure on that one. Laws are so strange and those who make them as well as those who implement cause of interpretation. States that have seatbelt laws but its not illegal to ride a motorcycle without a helmet.
Use caution my friend as if he ran your stuff as you said, he will be on the lookout for you to enforce the matter. Again, I would have better things to do with my off duty time.
Never grow up, it's a trap!