If they want to go digital, they need to emulate the best. I have a ton of games in my Steam librarysimply because they were so cheap. If they were priced at £55 doubt I would have any at all.
But Steam thrived because PC games were already getting reduced physical space in stores, to the point that PC gaming is now quite healthy despite having virtually no presence in many stores where console games are sold.
In any case, Steam is still an expensive way to buy games unless they're on sale. Plenty of other retailers sell Steam codes for less than Steam does themselves.