I'm confused by that decision too. I can understand the lack of earphones and charger in the box because everyone I know, even my parents, have various spare USB chargers kicking around their house. I never even took the charger, the cable or earphones out of the box for my last 4 or 5 iPhones so they're completely wasted on me.
But that logic goes out of the window somewhat when it comes with a C cable because not many people are going to have spare USB C chargers hanging around. I think they should have at least included a C to A adapter to give more people a chance there. On the plus side, at least Apple's fast charger (now 20w rather than 18w that came with the iPhone 11 Pro) is 'only' £19. It's not exactly cheap but it's better than the £30 or so they wanted for the 18w previously.