I use google for most things, for several reasons:

1. Google seems to have more data. Hours, reviews, photos, including usually more recent and frequent street views. They also have pretty good live traffic data
2. Access to offline maps. Nice to have a backup when you have no service. As far as I know, Apple Maps doesn’t offer offline maps except for your current route.
3. It syncs with my desktop use of google maps, including custom maps.
4. Apple Maps sucked when it first came out. Left a bad taste in my mouth
5. For navigation, unless I need an offline maps, I use Waze. Not part of Google maps, but owned by google.