I think that some player's are much too overprotective about discontinued hats, but at the same time it makes sense. Re-selling old hats would ruin that charm of believing that it would become 'rare' over time. Perhaps these discontinued hats should be re-sold, retaining their original price values, (excluding hats that could not be bought) bringing back 5 hats that would rotate weekly.
I honestly don't know what to think about this topic. There's nothing wrong with the way hats are currently distributed, but it would be interesting if this could be altered in a more interesting way. Alas, it is impossible to please everybody.