Well I agree, if they came across it illegitimately, then they have no claim against the Cuban government, and they were right to take it over. You're totally right about that.
But the "minority" who came across that legally shouldn't get fucked like that. An investor who hears that Cuba is gaining in tourism decides he's gonna go down there open a cigar business. He gets all the legal paperwork done with the Cuban government, puts down $100,000, and starts legally selling Cuban cigars. Then a new government takes over Cuba and they say they want to control all the corporations in their country. That's fine, that's their choice. So if this cigar company brings in 1 million a year, the Cuban government is absolutely right to take it over and have those 1 million dollar profits. But they might as well fork over the $100,000 to the owner of the cigar company because (1) the cigar owner didn't do anything wrong (2) international standards require it and (3) they would have made that $100,000 up very quickly if they weren't subject to trade restrictions based on illegal takings. Instead they cut off their nose to spite their face.
So "people like me" are not taking up the banner of people who embezzle, evade taxes, fund terrorists, sabotage, etc. I just happen to have an opinion that's different than yours.