Perhaps Linus’ belief in the Great Pumpkin is an escape from Lucy’s bullying (even though she, as usual, threatens to hit him in the TV special) and other struggles he has to face.
I understand why people love Snoopy. I love him myself. He’s just ungrateful most of the time, and this is not even the most extreme example! Poor Charlie Brown…
Don’t put words in his mouth. He doesn’t love you!