We tend to get carried away with germs and such. It's not like blades are made in the HepC ward. The germs on a blade made in Russia are the same germs as here in the USA or most anywhere on the planet.
I don't get too upset over blades not being sterile. Maybe I would if my immune system was compromised; then it would make sense to me. I won't use a rusty blade, but that's only common sense and probably not because of what you're thinking. Sure tetanus figures into it, but even more so, if I can see rust on a blade that means the edge is useless.
Remember the polio epidemic of the 1950? That was all because of keeping children away from germs and such. The children never developed their personal immunity to polio while still under the mothers acquired immunity. The first time they contacted polio in the environment, and it's everywhere, they contracted it. Prior to that the disease was rare or unknown. The case could be made that a few germs are actually good for you (not infections). That's actually what vaccines are. They're a controlled visit by a pathogen.
Brian. Lover of SE razors.