I don't know if this is true, but it seems that these Communists are comfortable with the protests being Communist. I would be afraid of either group appropriating the protests if I were in São Paulo. I didn't get the impression that this was a Communist protest. Is it possible that a protest against corruption and for fair use of tax dollars could be considered without assumed sympathy for established and storied left-leaning parties? If so, establishments on both sides of the spectrum poison the waters.
This is tangential to the matter at hand. I imagine it's very possible that parties on the right are trying to co-opt the protests in Brazil. However, both the Communists and the Fascists have a long history of implementation through oppression. I'm quite liberal, but to me personally, associating with Stalin's party is as distasteful as associating with Hitler's party.
Personally, I'd love to see a new progressiveness that has no tolerance for legacy code.