the term "guy" is mildly abusive.

Oh my goodness, I never knew that! Here, guy is a generic term for any male you don't know, as in "the computer guy",
"the telephone guy", or "the guy we saw at the mall". So,
guy doesn't carry any pejorative connotation at all, here.
If we knew the guy we saw, we'd say, "We saw John at the mall".

The things I learn at this place! Thank you all.