While no musical is responsible for teaching young people anything (except for perhaps High School Musical), Legally Blonde is very clearly targeted toward young women. So I would hope that it would have an uplifting message that might (just might) teach people.
At some point, wasn't the campy gay portrayl the only type of portrayl of gays that is accepted? Now there are soooo many viewpoints in theatre that is accepted thanks to groundbreaking pieces. Why don't we see more of these in huge musicals?
I think any writer needs to think about the material and what type of influence it might have on people. I know as a teen that there were plenty of theatre pieces that influenced what I thought and felt at that time. Some of those outlooks are still in place today.
I don't think you can just write it off because the gay community is accepted and a large part of the theatrical community. I really don't think this is well known by touristy/occassional theatre-goers. I just don't. And perhaps those who direct and act in shows forget that sometimes.
As for Spring Awakening, I didn't find it offensive in the least. It is just a stark difference between the portrayl of the gay and straight characters. That doesn't mean it isn't there for a reason (comic relief). However, it begs the question is it funny just because it is funny, or it is funny just because they are gay? I think Matt Doyle brings a bit more of the funny because it's funny to the stage.
So, that was the Drowsy Chaperone. Oh, I love it so much. I know it's not a perfect show...but it does what a musical is supposed to do. It takes you to another world, and it gives you a little tune to carry with you in your head for when you're feeling blue. Ya know?