Exactly my point... so as I see it there can only be 2 explanations:
1. This guy pretty much has spent a fortune on the community marketplace to buy up all those badges, which is an absolutely disgraceful waste of money - I just can't understand what would posess someone to do this
OR
2. The guy is one of the TF2 idlers with 1,000s of alternate accounts and has used his gigantic TF2 fortune to instantly trade to get all the cards + badges - This I suppose is better since at least it's just TF2 money effectively which was aquired for free
Exactly, it's most likely a mix of both 1, and 2.
Once you have enough badges and levels you get more coupons, and more booster packs. Which he can then sell or trade. So it encourages you to have higher levels to earn more booster packs, which get more badges, which up your level. So the cycle repeats.
This means that these people can end up funding their games collections/trading for free in the end, and actually end up making money later on. All with just a €100 investment in the trading card beta or at the start of the steam sale, along with TF2 item trading.
Personally I stopped playing TF2 before items appeared, I got burnt out by it.
I did get a 50% off killing floor coupon, which I used yesterday to buy the game and play with friends. I got enough cards to trade, got more badges and 2 more 50% off coupons.
It's all brilliant business move by Valve to encourage greater sales, plus the Community Market is gold mine for them, even with just skimming off 1-2 cents off each sale.