That looks like a porous egg to me (the one on the right is the one in question I assume?). Its normal, just don't wash them until just before you use them. When they're porous they're more likely to pull bacteria and such thru the shell, but if left unwashed the bloom will prevent that from happening.
I agree with howfunkyisyourchicken about the egg being porous. I would recommend that your girls have free access to oyster shell to make sure they are getting enough calcium (I assume they are on a layer ration with supplemental calcium already in the mix--if not then for sure get layer feed).
I give them oyster shell, layer, and i crush up the egg shells very finely and give that also. The eggs become spotted like that after 3-4 days sitting on the counter. Weird!
With my porous eggs, the shells are nice and thick. All eggs have pores, some just more then others. The pores are there when they're laid, you just can't see them at first.
If you shine a flashlight into the egg right after its been laid, you'd be able to see them, just not when they're fresh. I incubate alot, so this is something I check for. Porous eggs don't tend to hatch since they absorb bacteria (especially in a humid environment like a bator). I've had them explode like a bomb while incubating- yuck!