MLB has been pushing this “Hispanic Heritage” crap on us for several years now. The Pirates also had a Spanish jersey which read “Piratas”. I recall once a player wore one by accident during a non-Hispanic Heritage game. The umpire caught him in the 3rd. inning and set him off to change.

Of course many teams have Spanish language broadcasts of their games (el juego de las medias rojas de Boston esta...) and I think one station in LA does 'em in Korean, right?
They're appealing to the hispanic audience in this way (much like they may have kids' events, gay-friendly events, etc.---or "it's Vermont Day at Fenway Park".
But I know what you mean.
One time ESPN Sunday Night Baseball was at Wrigley and there was a malfunction that made it impossible for the Eng language broadcasters to be heard so they put the Spanish language ones on, for the time being, en ingles.
Certainly a lot of players are hispanic. And we know for years blacks were excluded, but now many are huge successes ("get those n-----s off the field" was said by one club owner during tryouts--back then...)