Or the screws *were * there and are now rolling around in the packaging or delivery truck. Don't suppose the screws have star-washers so they can't shake loose do they?
Found these under the flap at the bottom of the box.

Hopefully the blades banging each other during shipping didn't damage them too much.
They need to be using something like these machine screws w/star-washers that are part of them
http://www.mcmaster.com/#95345a047/=riqrv4 also available with sheet metal threads.
Not true. Even with Star Washers, tightened case screws DON'T just pop out in transit.
This was either intentionally done (damaged on purpose to blame Fedex) or these weren't tightened at all and fell out due to vibration in transit.
Hard to believe.