Their criticism of Gloria La Riva is flawed, too. 

Did I miss something, or are they silent on the Worer's World Party ?

I was an active Green for years,and there were a lot more upper middle and upper class liberal types in my branch, than working class people. This does raise the question of how sincere someone's commitment to radical change can be, if they have benefited enough from capitalism. Would they choose class over revolution, should the choice arise. I know about Engels, I know about the family background of Fidel Castro, but I think we should view people of money and means with suspicion, until they have proved their worth to a party or movement. Every revolutionary party, or organization, does need sympathetic financial backers.

Small business owners are technically petit bourgeoisie. Their support can go either way. Are they workers? Definitely. Are they part of the working class? That's open for debate.