though this is a non issue anymore, others are right that this issue could reoccur. the one behind tbe spam transaction can go and spam the network again. hopefully segwit would be enough to counter those attacks so the fees will not rise again. though the miners benefit from those attacks, i do not think they are behind it.
If spam transactions include a fee they are not really spam. Bitcoin needs to be able to handle dust transactions to be useful for all applications anyway. I think side chain solutions are what will enable it and segwit is an important part of making that happen.