My 5 year old got his first pins and lanyard in DEC. When we saw the Pin Board at AK we stopped to look and he traded one of his pins. Trading is out there, just not as easy as before.
side note: I always wear a few pins. I have a Baggalini with a great shoulder strap for pins. I had a teenager approach me asking if I traded. I smiled, and just said "sorry, I really love all my pins and don't trade". He was so gracious. Trading Pins doesn't seem to be the "IT" thing it was but it doesn't stop me from showing them off or buying more.