I had a problem (long ago) and our ups would freak out from time to time. I stuck a volt meter in the wall socket and set it to record. the results were troubling.
I called the power company and they came out and put a recording meter on our circuit. a few days later they came back and showed me a paper graph of just how 'dirty' the power was.
I think they replaced a transformer down the block or something, it fixed the problem in any case.

so yes, I believe it does happen.