Loose notes

Loose notes description:
I don't understand how police can seize and charge you with illegal currency for having loose notes. The description it doesn't say there is any valid reason those should be flagged as being illegal. There is nothing that would set loose notes apart from just having random cash in your pocket. The fact that police are so adamant saying its illegal with no proof feels wrong. I would understand if the notes description said something like flagged money or marked money but it doesn't.

I feel like if they are gonna charge you they need to have proof or a way to link it to a crime and not just say its illegal. I gave a reason to have them. What I planned to do with it and they still said it was illegal because its in the penal code. But What I am asking how can they tell the difference in the money when the description doesn't say anything that would determine the legality of the bills.

I totally get that its illegal but there should be something in the description that gives them a reason to flag them or at least a stronger argument to how they can tell them apart from legal bills.