Why do random girls know my name?

Several times, random girls knew my name and were like "hi nick" and I never talked to them a day in my life. What is up with this? This happens more than once, and I'm beginning to think something bad is going around campus about me? Rumors? Lies?
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+1 y
I don't want to insult them or anything and ask them who they are.. So I just say hi and move on.
Updates
+1 y
OH and then some random dude knew my name a couple weeks ago. Which was really weird.
Why do random girls know my name?
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