I'm not as familiar with ETC but can you choose your fee? It has happened with BTC in the past where someone put the amount they wanted to transfer in the fee and the amount they wanted as the fee in the transfer portion of the transaction resulting in an enormous miner fee on the block that included the transaction. Does ETC work this way? Maybe someone is dumping coins to miners on purpose?
Yes, it works like most other coins AFAIK and I checked it, someone with a huge balance is donating crazy high fees to pools and miners! I got one scenario:
There is some ASIC manufacturer with tons of hashpower ready to attack Ethash, he is paying coins to pools while their reward system calculate shares for miners. Now this is the trick, pools are payed through coinbase of mined blocks that will eventually become orphan and coinbase transactions are not matured anyway, but miners (probably the attacker among them) are payed from pool operator's old wallets. The attacker then puts himself in charge of the chain, restores his original balance and pools are ripped, just pools! It is an attack against pools, I guess.