Why is Halloween a positive thing for August?

From the text:

For me, Halloween is the best holiday in the world. It even beats Christmas. I get to dress up in a costume. I get to wear a mask. I get to go around like every other kid with a mask and nobody thinks I look weird. Nobody takes a second look. Nobody notices me. Nobody knows me.

What were jack and Julian talking about?

Because he can cover this face and people can think nothing is wrong with him and his face and also he loves candy and get some