They're used a lot in English (and to a smaller extent in Swedish) and I'd imagine that they exist in Russian too. Are there words in Russian that correspond roughly to informal English words such as "like," "whatever," "nevermind," "sort of," etc.? It'd be hard for me to imagine making a sentence in English without saying "like" or "ummm..." or some other form of stop. Sometimes in English they obscure the meaning of a sentence so much that it's nearly impossible to comprehend!
BTW, if you're an English Nazi, please excuse me if "verbal pause" was the wrong term to use.