I've always thought that Freds were any biker who didn't care about what they looked like. It helps to have as many acoutrements on the bike as possible. I see commuter Freds, but I also think of many tourers as them. This is due to personal contact, and with the Phred.com website. The best Freds I've seen were on RAGBRAI--the bike tour across Iowa. These are the people with streamers on their handlebars, and teddy bears strapped to the front, giant mudflaps, beer cooler on their backrack, shnapps in the water bottle etc. Most of them seem to be well muscled tourers. One Fred I knew would bike with ALL of his gear from the Mississippi to the Missouri River, and then follow RAGBRAI back to the Mississippi. He also strapped his guitar on for nightly entertainment. He put a pillow on his seat and had a huge amount of foam pading on his drops. In town he road an old cruiser with Wald baskets while wearing big work boots.
Another Fred I saw on RAGBRAI rode what appeared to be the kind of bike I had as a kid in the '70's. It had chopper bars, probably originally had a banana seat, and chrome fenders. He had raised the seat and bars up to adult height and had front and rear panniers loaded with all his gear--no sag wagon for him. I heard he rides the whole tour that way. It's almost a contest to be as ridiculous as possible--but these are serious riders.
The whole Fred thing remids me of the movie Quadrophenia and the battle between the Rockers and the Mods. The tough guys rode cool motorcycles, and the Mods rode around on scooters with ten reflectors, too much chrome, streamers, everything. They got beat up by the Rockers. But I always related to them better. I only wish I could be a Fred.