Getting autograph of stephen curry, gaurd got mad?

I went to the celtics vs warriors game and at the end of the game i had a p to go shoot on the floor, and stephen curry came out and was signing autographs. i took of my high top nike (it was gold and sparkly) and i was waiting in line for him to sign it. the gaurd looked up and me then my shoe and shook his head with almost a condescending look. why would he do that??