Why does a bottle of water at a ballgame cost $5, at a food truck $1, and at a supermarket $0.15?

Personally, I find the ballgame price exploitive, but the food truck has added a bunch of convenience (and a few pennies of refrigeration cost) and that's worth paying $0.85 extra to a lot of people.

Companies try to set prices to either maximize their profit or to bully out competitors at a net loss.

You can translate "the market can afford" to "customers are still paying".

Difficult to calculate that given lock-in. If you've outsourced everything infrastructure related, you aren't in the same market without substantial upfront investments being made.

Amazon/Google/Microsoft/IBM et al. all know this, it's why there are significant incentives if they know you can walk.