Yes, it's an R-rated movie, but you would have to be incredibly naive to think that the only people who see an R-Rated movie are thoughtful enough to know "it's just satire". There are way too many ber-swilling idiots out there who will just love the line.
And assuming they don't let their kids see the movie directly (yeah, right, how many people under 17 actually see R-rated movies!), those kids will still be the beneficiaries of their parents' talk and the marketing campaign surrounding the movie.
My daughter has Mental Retardation. The verb "To Retard" is defined as "to delay or hold back in terms of progress, development, or accomplishment." Yup. Sofia has delays in her progress and development.
But the noun "Retard" is considered an offensive word. Just like lots of other words that I do not want to type: the N-word, words that are used to negatively describe Jews, Chinese, Japanese, Hispanics, Italians, Lesbians, Gays, Irish, and any other group you can think of. If a movie made a big scene about "You Never Do the Full ***" (fill in a slur), that group, and hopefully many people NOT in that group, would protest.
But people with Mental Retardation don't necessarily have the ability to protest by themselves. So we, their friends, family and advocates, must do it for them.
Do I think the movie should be pulled? No. It's a movie.
Do I think it should be boycotted? Yes. Register your anger.
Do I think Stiller and company owe an apology? Yes.