How do you deal with a vain, toxic employee at a local business?

i meet this person through there work and if i didn't see them at there work i wouldn't see them anywhere else despite the fact we live in the same area.

i really don't know what is wrong with them exactly , they got promoted a few years back to a position there really not qualified for and it hasn't really worked out yet owner has allowed for them to stay in it anyways. and they seem to have no interest in finding another job.

so i see this person at there work a lot , ( i'm there as a customer if your wondering i don't work with them ) but this person just comes off as seriously a train wreck really and they seem to hate half the customers who frequent the business like myself.

Updates
1 mo
she still works there but looks like she is about to have a nervous breakdown or something , like serious whako , can't believe she has stayed there that long , not even sure what she brings to the business or why owner would want her there so badly
How do you deal with a vain, toxic employee at a local business?
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