Back when I was in college, nearly 25 years ago, I spent three weeks during winter break as a security guard in a large downtown parking garage. As the downtown in question was in a declining Rust Belt city and even back then had lost many of its merchants to suburbanization, the garage was largely empty. I walked around for my eight-hour shifts with literally nothing to do. Not that I would have been of any help if some sort of incident had occurred, as I had been given no training whatsoever.
"Let me think about it" = the coward's way of saying "no"