Without their explicit consent, its miners were coerced to participate in an attack led by the pool operator, ultimately stalling the operation of the fledgling cryptocurrency CoiledCoin by mining empty blocks.
But you know that the popular way of implementing Merged Mining is not what Satoshi intended? NameCoin made the same mistake: there should be one chain of block headers with the heaviest Proof of Work, Proof of Stake, or Proof of Something, and each Merge-Mined chain should receive a fraction of coins proportional to the whole power of all chains. In this way, attacking any altcoin by reaching 51% power, 51% coins, or 51% something is possible if (and only if) you have a majority on all chains together. And of course people didn't implement Merged Mining in that way. Also, when it comes to Proof of Stake, there is an alternative called Merged Signing. And guess what: people are still unaware of that, and they still think that creating new coins will make the whole situation better, but nobody gave any reason, why it is needed to create new coins at all, instead of signing existing coins from other chains, and build new protocols on top of that.