Speer and Federal are ATK. Some of their things are identicle but not all. Their products are like GM. A Chevy and Buick might have the same engine, but not necessarily the same breaks.
Winchester is Olin, a different company.
I agree with the others and think that a couple here and there is nothing to worry about. Those could even be someone else's brass that migrated into your collection and they might have beaten it to death before they left it behind. Entropy happens.
Drugs are bad because if you do drugs you're a hippie and hippies suck.
"If you kill enough of them, they stop fighting."-General Curtis E. LeMay