I have never heard of that, I have heard of the expression of a Bannana Republic as a derogatory remark against developing countries. I am half Brazilian and have never heard the term bananero or bananeiro... well I have heard Bananeira which is where the fruit comes from. It wouldn't make sense anyway since Brazil was never a Spanish colony.Johnny Novgorod said:Jesus, everybody got this wrong. They're not attacking him for his race, they're attacking him for being from South America. It's very common in Spain to be condescending towards "bananero" countries, i.e. countries that are stereotypically said to live off banana exportations. The implication being they're culturally backwards countries. "Bananero" is their go-to insult when attacking us. It has nothing to do with race.
I have however seen and heard of Banana's being used for comparing black people or non-whites to sub-human apes, both on and off the pitch.
And as other posters have mentioned banana's aren't have been thrown on the pitch before, and aren't the only things that racist hooligans do at matches. Most commonly they shout chimp calls at or other obscenities. That incident was about racism, there is no doubt.
Football in Europe has attracted a lot of racist hooligans, I'll give you an example English team Tottenham and dutch team Ajax, have both been mercilessly heckled for being Jewish, all kinds of ugly things, why? They are not owned or contain a large number of Jews now, but in the old days both teams accepted immigrant Jews into them at a time when Europe was less tolerant of the Jewish people. The racist insults that began back then are still present now.
Hell even wikipedia has a page dedicated to it
http://en.wikipedia.org/wiki/Racism_in_association_football#Europe