What bugs me a lot...

I hate it when people express some interest into a topic that I'm happy to explain, and then once I'm half done, my audience clearly loses interest.  I mean, I'm not a really long winded person (even though it sometimes feels like I am.) I won't give you an hour lecture on how Mozart influences dubstep.  So when my father asked me what dubstep was, I tried giving him a good explanation.  I couldn't really give a great answer, so I decided to show him once we got home.  The thing about my father is that he's a very busy man whether he is working or not.  I tried showing him a good example of dubstep (Skrillex).  Literally not 3 seconds after the bass drop, he left to do something else.  Like hello?  I remembered that you were interested, but you gave me a slap to the face as an audience just by leaving in the manner you did!  I get it that it's around dinner time and the table needs to be set.  I'd understand if he just said that.  However, he didn't.  He just left, without a word.  He does this consistently.  Not just him, but my mother too.  I wonder if other parents do this to their kids as well.
They say the older generation can not stand the culture the youth are creating because they don't understand it.  I'm just trying to show them the culture I enjoy.  But if the older people don't even try to appreciate it, they never will.  The same goes for the younger generation.  If we as children and teens do not try appreciating older culture then we never will. 
If you're interested in someone else's hobby or interest, don't just leave and give up silently.  At least have the courtesy to say that you've lost the interest in the topic.  At the very least do that.  Otherwise you seem really offensive.