We’re guessing this impeccably dressed gentleman was tired of shouting his order through a perspex soundproof barrier and decided to get his point across by shoving his upper body through the order window.
Gotta respect his initiative.
Apparently, this peculiar behavior is becoming quite the phenomenon at McDonalds branches in China, with many customers acting “overly familiar” toward the company’s staff. Personally, I think the guy just got a little too eager and wanted to make sure the cashier got his order right. Hey, at least he’s got his priorities straight.