Social Awkwardnesses

Tonight I went to the store to get pumpkins, and what not, while checking out the girls were talking about a casserole that you make inside the pumpkins.  Just to make conversation, I said Really?  So, she also just making conversation said, Weird huh? My only response to that is yeah.

All of a sudden some bagger comes out of nowhere and says, 'actually, these pumpkins are squashes, so it's not that weird.  People cook squash all the time... and on and on about how pumpkins are really squash, but different than real squash...  I kind of ignored him to answer the check out girls questions if I wanted cash back, etc. So, he just stopped in mid sentence and said sorry.  So, I of course then felt obligated to say, no, it's interesting... and then had to listen to him tell me that he's really a farmer (from denver!)  I don't know if I'm weird or what, but I hate leaving someplace with that feeling like I just made someone feel like an idiot.  Instead I end up feeling like the idiot.  What is wrong with me?