I don't have any children (and I don't plan on it..ever. I told my parents when I was 12 that if they wanted any grandchildren, they would need to wait until my baby brother grew up. He now has 5 kids.
But if I had a child (a son in particular) and they were one of these boys that developed a purse fetish. How would I react to that? How would I handle it?
Honestly, if this did occur. I would just take it in stride. Sure, if I didn't have that sort of my fetish, myself, I may have been kind of freaked out by it. But then again, since I do share that sort of interest. I would be more understanding about it. I would sit down with him and want to know everything about why he feels the way that he does. What started it, when did it start, etc. But I wouldn't judge him for it. (Due to the aforementioned thing).
I would find out which bags he had been using and if I didn't use it, I would give it to him. If it had been one that I were using, I would tell him that one was off limits. Then I would pick out a dozen bags and tell him that he could pick out four from that dozen. Then I would tell him that my closet would be off limits from that point on. If he wanted another bag later on, we would work something out.
Now, if I had a husband, that would make things a bit more complicated. But if I were a single mother, that would obviously make things easier. But if a husband were in the equation, I would just work around that. It would just be something between my son and I.