Everytime I've pulled my fuel system, there has been a minute amount of rust on the outside of the high pressure connector tubes (pins, needles, whatever you want to call them)
The first time I pulled them, they had a pretty good amount. It was surface corrosion only, but that's where it starts. Being down south, we don't get the salt and harsh winter crap either.
I've made it a point now to lightly oil them, when I've taken them out.