The false dichotomy between "need to" and "because they can" is at the root of a lot of sloppy economic thinking. It's true that businesses aren't trying to charge the bare minimum they need to survive, and that this sometimes lets them absorb the cost of providing service X for free with no hit to consumer welfare. (This can happen for both regulatory and non-regulatory reasons - furniture stores, for example, will often give you quite a bit of free employee time in hopes of catching a sale.)

It's not true that business costs are entirely fictional and consumer willingness to get hosed is the only input to their pricing models.