It isn't just about having the network. Realistically, very few people would sign up just to use a single network or Charging Point Operator (CPO) is they're known in the industry. They then sign up to EMSP (eletric mobility service providers) and the EMSP have contracts and connections to a bunch of networks. Then there are hubs, the CPOs depending on their size can't handle all the work that comes with being connected to all the EMSPs.

Shell as far as I can tell own a major EMSP and building their own network.