Or, you can create an account after investing a few hours or so into the game, at which point a bit of friction is irrelevant. And sure, the credit card details

Or, you can create an account after investing a few hours or so into the game, at which point a bit of friction is irrelevant. And sure, the credit card details will have to be entered eventually, but again, you'll be very invested at that point, so a bit of friction doesn't matter. Regarding the CDN costs, with some very aggressive caching (Service Workers and stuff), is it really that much worse than a downloaded game? You're the one who actually has a game, though, so I guess there really is a problem here.