I don't think most of us are confused by that line. And just because it might not be meant as a slight against adopted children, doesn't mean its not offensive to some. In my case, it was an issue that needed to be discussed. For us, the intent doesn't matter - its still there and had to be dealt with.
And a lot of things in movies need to be dealt with subjects that might be sensitive to some viewers. When the first
Spiderman movie was released less than a year after 9/11, news outlets in the NYC area did warn parents that scenes of Manhattan being attacked by Green Goblin might be disturbing to children who had seen a real attack on the city just a few months earlier. Doesn't mean that they were trying to offend people.
Intent does matter. Someone saying
The Avengers meant to offend adopted children simply isn't true. Anyone saying that people who laughed at the line (which I did) are some kind of heartless creatures who don't 'get it' isn't true either.
It was clear the intent of the line in
Avengers was not to say that adoptees were bad, it was just an awkward, out-of-character backtrack from Thor. Saying that this movie
intended to do something like that to someone other than Loki with that line is just not accurate.
Saying that the line was bothersome because of a personal situation? That I understand. You can talk to anyone and they'll tell you a movie that made them cringe because something in it came too close to home, even if the movie wasn't going out of it's way to personally attack them.
I see that this subject has been somewhat controversial in other movies such as
Tangled, Lilo & Stitch, ELF, Annie, Meet the Robinsons, and
Despicable Me, where adoption, or orphans, using the phrase "real parents" has been a problem. But I've seen those movies - like the line in
Avengers, using these characters' situation as a plot point was not intended to offend, or send some kind of message that an adopted child is less than any other child.
The "it's harder to love an adopted child" tagline on the movie poster for
Orphan a few years back was offensive - it's an R-rated horror film, but that was on a poster that any kid at a movie theater could see. And the studio was smart to change the line on the poster.
I can totally understand why the
Avengers line might have hit a nerve. But I won't say that the movie intended to do so, because it didn't. I'm not going to petition for the line to be removed, because it clearly wasn't the intent of the line.