1. Google gets a lot of this data from their users (both from traditional crowdsourcing and sneaky things like tracking Android phones) and then locks it up so you have to pay to use it.
2. The way they license their services forces you to stay in their ecosystem. For example you are only allowed to use Google Places Search on a Google Maps map.
3. There are APIs Google just doesn't provide for various reasons and because they "own" the data, everyone else has to start from scratch (or use OSM). There's no way to download some subset of the data for a one-time sum or even a subscription license and provide your own service on top of it.
Yes, these things mostly fall into what people consider a company's freedom to do business however they like. But Google is more than just any random company and the data they gatekeep is more than just any random dataset.
