Well for starters they probably track your location within the boundaries you gave the app.That old trope. I bet you don't even know exactly what data they collect and what they do with it, other than saying something very generic like;
They track you.
They sell your data.
Then they probably track your searches
your taps on the map
POI you check
directions
I just don’t want Google to know where I live, where I want to go, what businesses I’m possibly interested in, etc
Just because it’s old trope doesn’t make it invalid