You would have to own a majority of masternodes in order to attack instant transaction locks. The cost of acquiring this many nodes (currently about 1.7 million DASH) would be prohibitive, as there is obviously not that much available for sale and even if there was, the price would skyrocket if anyone tried to obtain this much.
AnonyMint wants a system that is NSA/state-resistant (well who wouldn't?), and a system where the state with its limitless resources can buy/bribe most of the masternodes does not pass the criteria. Current holders could become filthy rich in the process but the end result would be a government controlled coin.
Except that we can deduce pretty well how many different people own Masternodes. To break the system, we know a person would need to control at least 90% of them. At this time, it is no longer possible to do, government or no. The budget would very quickly become huge, and that would require conspicuous approval to spend so much money (and I think only the only countries with that kind of wealth also have enough checks and balances to need approval) Otoh alone owned as much as 20% of what we have today. So I doubt we caught Governmental attention early on enough for them to have made a move. You could argue the same thing with the huge mining farms that seem to control bitcoin mining. Or the pools. I think it doesn't give enough of a guarantee for a Government to invest so much, to receive so little, and questionable little at that.
No, thinking that Masternodes are in any way a weak link is completely illogical. And when it comes to Crypto, logic wins over emotion.
Then you would have to ask yourself, who would want to get into a filthy bed wit a government? You would be giving up your control over YOUR privacy by letting them into YOUR house. I don't think people who invest in this coin, certainly 99.9% of them, have warm fuzzy feelings and trust enough in their government to do that, and to get enough to turn to make it worthwhile for the Government, well, it's just not going to happen.
Since I'm not a socialist, I can't be bothered with the "but it's so unfair that some people will become rich!" argument. Those people who support new technology enable the technology to happen, and thus have EARNED their wealth. They supported something that will eventually harness a LOT of work, which is what ultimately makes money worth what it is. If Dash can harness and make available work, easier and cheaper, it will be worth more and the project will have BENEFITED mankind. Just like the desktop computer did, just like the car did, just like the railroads and steam boats and horse and buggy and wheel did.