As a former radio announcer, I can tell you it's inexcusable for an announcer to repeatedly mispronounce words in his or her area of "expertise".
As to sports announcers doing this, I have to admit I don't take it a seriously as our President always saying "nuke-u-ler".
Probably the two most mispronounced words I hear on an ongoing basis just in the business world are "realtor" (it is not "ree-lit-er") and "jewelry" (it is not "ju-le-ry").
Also, Juulie is not pronounced "Joo-ooo-ly" but is correctly pronounced "Fish-net".
