I noticed during my half marathon run that people were discarding everything from headbands to socks to shirts and mittens. I have never seen this on a 5k run so I have no clue what people do with those discarded items. I'm guessing it all gets tossed out.

Having spectated both professional golf and marathons, I'd have to disagree. There is far more entertainment watching marathons. You get a wide variety of people to watch, from crazies to hotties. You never have to be quiet, and you never have to hear, "Get in the hole!" And it's BYOB.

The clothes are usually donated. When you plan on running for 2-5 hours, you get hot and don't have much choice other than carry the item for 26 miles or toss it.

Cheers!