A more interesting question for me would be: For those who do garnish your stories with real places or events, why?
There's a certain amount of "write what you know", I imagine, and being able to describe a story that takes place in London or Seattle with realistic detail helps the reader immerse themselves in that world. In my case, the characters in my series are based on myself and my spouse, but the situations depicted are... let's say "aspirational" fiction. I wanted to take our sex life in a certain direction, and these stories were me trying to forecast how that would work.