They are probably not even (predominately) Sander supporters.
They are trump/GOP supporters mixed in with the protests.
As if we don't know that GOP supporters are at the protests surrounding the convention .... Duh.
Yeah, because Republicans have nothing better to do than to shill for Bernie of all people.
Yes, trump-Pubs have "nothing better to do".
They decided to take a break from their dominant theme of spreading hate, racism and fear ... and instead show up to protest using other childish methods.