I went to get a fresh Bic blade to put in my FaTip razor, since the old blade had seen 9 passes and was noticeably dulling, and the new 5-pack I opened had 4 blades, and one empty blade wrapper. I bought 100, and only got 99! I'd probably be more bothered by it if blades weren't so cheap, relatively.
Have you checked all of the other packs? I wonder if you wrote the company if the would send you one new unwrapped blade, since you did get the wrapper?
I wouldn't be at all surprised if there were a blade discovered on the factory floor in Greece, on the day my blades got packaged.