Also, satoshi nakamoto himself used the block chain in this "abusive" manner by embedding a message for the bankers in the first block. If satoshi didn't want the block chain to be used for other activities than purely monetary transactions then why on earth did he do it?
I think it was probably a pity that Satoshi actually did that (of course you know it was to show that there was no premine) as unfortunately his approach has been used by others and then extended through other approaches (I even worked out how to encode information in the sigs themselves although I've never actually used it live - come to think of it that is actually perhaps a better approach as it is just reducing the signature entropy a little and doesn't actually waste space).
It is inevitable that such pollution is going to happen and limiting dust is (at least for now) about the only reasonable method to preventing the UTXO set getting too large.
Since that is part of the coinbase script, it isn't related to creating normal transactions to put data on the blockchain. The coinbase script can have anything you want in there, that is its purpose. But encoding data into addresses or as part of OP_RETURN isn't really something that is condoned.