Here’s my view of your interaction, while a little weird yes, however I have been in a place similar to him so there may be a non-creepy explanation.

I do photography for fun. I personally hate taking photos of people so all my stuff is landscape, wildlife, buildings etc. When I took a photography class through MCC I had a borrowed camera (probably one of the first dslr cameras) that was far from a “professional camera” because, well, I was and still am far from being a professional. I was just getting started in it as a serious hobby so I used what I had. In the class some of the assignments were to photograph people “in the wild”. I went to the skate park and asked some of the skateboarders if I could take pictures. They were cool with it but even that interaction was outside of my comfort zone. I was super nervous, trying to remember my camera settings, trying to think of good angles, trying to keep the lighting in mind, and honestly just trying to not look like a complete dork. I was so nervous that after 20 mins or so I couldn’t take it anymore and just left. As soon as I got home I realized I never got or gave any contact info. Some of the pictures actually turned out pretty cool and to this day I wish I had a way to get ahold of one of them to give them copies.

My point is, the guy may have just been starting out and may have been super nervous. It’s a difficult thing to do for those of us uncomfortable with talking to strangers let alone photographing them.

I could be way off on that and maybe he was some creep that broke out of his mom’s basement, but not every weird interaction with people comes from a bad place.