Maybe I missed it in the article, but I don't see a legal basis for confiscating their money. Based on what I'm reading, the DOJ is going after their stash because they believe they should be broke. It's not necessarily against the law for the accused or even the convicted to tell people they believe that they're political prisoners, nor is it against the law to set up a go-fund-me to pay for legal bills, loss of reputation, etc.'
If they owe restitution, fines, penalties, and they want the proceeds to make those payments, I could possibly see that as a rationale for DOJ action, but the way the article reads, this is just the feds imposing their own extra-judicial form of justice on them because they're angry at them.
FWIW, I feel the same way about these bozos as you do, but the judge and jury should determine the penalties they pay, and once they've been through the legal ringer, maybe it's time for people to move on.