+1 for Common Sense
When you really think about it in a global way, storing data in a second blockchain is even more wasteful.
Imagine these two future cases:
Scenario 1: Bitcoin + Counterparty
Scenario 2: Bitcoin + BitcoinLikeSecondChain + Counterparty
Scenario #2 will always use up more data globally than #1 because we have to add in the second chain + its overheads.
Scenario #2 makes all parties (Bitcoin, BitcoindSecondChain, and Counterparty) a little less secured.
Why have Counterparty/metaprotocols running on top of a second chain when it's even simpler to integrate directly into the chain like some of the Bitcoin competitors? Why even have OP_RETURN? Why even have script if we really want to save every bit of space?
Counterparty is just tiny writings in the margins of the Bitcoin book. Reducing the margin to 40 bytes and advocating that all metaprotocols write to more books is just encouraging more wasted resources for everyone on the planet -- just so we might save up a few bytes in one book.
Allowing just enough room in OP_RETURN for a hash is like leaving enough room for Fermat to write down one last equation when that one equation could have led to another, and another in a chain of discoveries. It makes sense that a little more room for writing in the margin will make the Bitcoin book more valuable for everyone NOW before the new competitions come.
Please allow some room in the margins instead of encouraging metaprotocols to waste more trees by starting more useless books.
It is called a free ride. Given that the overwhelming majority -- >90% -- application for the bitcoin blockchain is currency use, using full nodes as dumb data storage terminals is simply abusing an all-volunteer network resource. The network replicates transaction data, so why not come along for a free ride?
Rather than engage the existing community, mastercoin and counterparty simply flipped an "on" switch and started using bitcoin P2P nodes as unwanted data stores. An unspent transaction output was never meant to be used as arbitrary data storage. The fact that it can be abused as such does not make it right, or remotely efficient, or the best solution.
The UTXO (unspent transaction output) database is the entire network's fast access database. Every single node needs that database to be as small as possible, for best processing of network transactions. Encoding arbitrary data into unspent outputs is network-wide abuse, plain and simple. The entire network bears the cost.