We found a balance with MIT+CC, you can indeed fork, change it, sell it, the intention is Commercial Limitation; ie cloning the whole code base and starting a competing product as it was done. Funny enough little on the hard stuff we built that was clone has changed on the fork.
Imagine Bitcoin developers started changing BTC open source code to CC after first shitcoin forks showed up 
Lame excuse from you nvK and I don't agree with you that nothing or little was changed in Passport wallet, but it's not very hard to compare two github repositories to see the difference, so I don't have to trust your words.
Someone could correct me if I am wrong, but I think that you also didn't release your Seed XOR (version of Shamir Secret Sharing) as open source, just showing how wrong your thinking is.
But hey, do whatever you think is best for your product, if you are selling better than ever like you say, you have nothing to complain about.