I apologize if I give offense while attempting to shed some light on why people have a problem with your company (and those who choose to work there). It's difficult to be honest about this question without coming across as mean, but I will try.
1) wholesale copying other companies' games (see http://www.scribd.com/doc/101954002/EA-v-Zynga-Complaint-Fin... for a legal complaint and http://news.ycombinator.com/item?id=4335287 for discussion.) From that thread: "they must realize that every day they go to work and rip off someone's original work." It's hard to respect someone who knowingly makes their living this way.
2) The game mechanics of Zynga games often hinge on what might be viewed as "bad" use of psychology -- manipulative, addictive, and in a sense abusive of the friends functionality of facebook. It's hard to respect someone who knowingly treats people so callously.
3) Common opinion is that the games themselves range from mildly awful to completely terrible, and are successful almost entirely due to the "bad" psychology above. It's easy to respect someone like notch, who got rich making an awesome game. It's hard to respect people like Pincus, who got rich by making games that are fundamentally lame.
Again, no offense meant to you or your friends. Maybe you're on a team that doesn't do any of the above bad stuff. But the parts of Zynga most of us are familiar with do all of that bad stuff. I hope this helps clarify why you might see so much hate directed that way.