An EULA ("End-User License Agreeement") has to do primarily with copyright (17 USC [1]). As such it's pretty much orthogonal to the criminal statutes related to this act of "misusing" cryptocoins.
> next generation of cryptocurrencies can have a simple EULA
This is anathema to the nature of cryptocurrencies, all (?pretty sure all that matter anyways) of which have Open Source implementations.
Really, most cryptocoins which are worth anything have already had a big market cap "bounty" that has effectively proven their safety.
We don't need a EULA. Like I said, you could maaaybe sue for damages. Unfortunately there's no easy way to undo the impact to a coin's reputation once it's shown to have a weakness like this. Even once the bug's patched and the nodes all get back on board, exchange rates will suffer for a long time.
You are getting attacked for poor wording.
It's reasonable (and there is precedent) for something like a blockchain fork that voids the value of bad coins. You'd need some implementation of majority vote, though (a jury of your peers, weighted by hashrate?)
Government censorship of coins or transactions is an attack vector, not a feature.