Okay, so on the Infosphere it says this about Fry falling into the Cryotube:
He quickly hits the ground, flips upside down, and finally stops once he hits the inside of the tube. If that had really happened, the beer in the can he's holding would have spilled all over him.
If you spin a bucket of water 'round really fast the water does not fall out. Look at how fast Fry falls into the Cryotube. The Beer wouldn't have fallen out.
You are assuming that Fry's speed was the same as the bucket's, though. A human would most certainly fall much slower. Then again this is comedy, so I still wouldn't call that a goof.