No, I haven't. I've seen some really nice things with Cast Members.
One in particular, at Pizzafari in Animal Kingdom a few years back, there was a very 'difficult' group of guests in front of us in line. They were being so rude and nasty to the poor young CM. She looked like she was almost about to cry. Just then, an elderly CM came over to her, very nicely put his arm around her shoulder, and said quietly and sweetly, "It's okay. Let me take care of this. You go take a break for awhile, okay? It'll be alright." He was so kind to her. My kids have been back a few times since then and they still talk about the kindness of the elderly CM to a fellow CM.
Another time, also at Animal Kingdom, it was a quieter day, and after going through the turnstyles, we stopped to put our cards away. We overheard 2 CM's talking close to us. They were talking quietly, but we could hear. One was noticeably upset about something...turns out a family member was having a major health issue and it was just really upsetting to her. It struck me that even though Cast Members are supposed to be "in role" at all times, in reality, they struggle with real life just like the rest of us. It must be so hard for them sometimes to be so upbeat when after their shift, they go back to the 'real' world. I really commend them for making me and my family feel so special.