Now that I remember the context, I'd say Telly wasn't trying to be mean at all. A lot of people who are friendly to each other usually call something lame. It's not so much mocking Chris, but rather saying, it would be pretty lame if all we did was pretend to look like shapes when we can do it. It's not so much bullying as (if anything) gentile teasing. Plus, if you think about it, Chris's assumption that all they'd do something like that could also be taken as an insult to them.
I love Charles Schulz, indeed I do. I know about his personal anxieties and all, but somehow, I think his stuff's a little on the mean to his own characters side. But for every kid who was mean, they had something else wrong with them. Lucy is the prime example. She bullies the heck out of Charlie Brown and her own brother Linus, but on the other hand, she gets no respect or love from Schroder, who she's constantly pining over. I don't feel that most of the kids hate Charlie Brown, but they have cliques (I blame Violet... thank frog she's not around much anymore... she's WORSE than Lucy), and they force him out of them. Linus is the most level headed, most intelligent one in the group, but he's got a crutch with his blanket. of course, what also is amazing about good ol' Chuck is he's too blinded by his own inadequacies to notice a lot of the kids do indeed like him (something some of us experienced). And while he's pining away for the Red Haired Girl, Marcie and Peppermint Patty are all but throwing themselves at him. Any other cartoon character would have settled down with either PP or Marcie (I'd go with Marcie... she's like Velma of Scooby-Doo... the type I prefer, actually), but Charlie, for all his short comings that he knows of and what he's capable of still holds out hope for the Red Haired girl. Meanwhile in Garfield, Liz the Veterinarian actually broke down and admitted she does indeed love Jon.
And Snoopy was pure escapism.
The underlying psychological bits of the Peanuts fascinates me.