That's a terrible analogy because an all you can eat buffet is effectively unlimited but as I already mentioned the number of images was limited.

Your comparison is actually more like if you just ordered a regular meal and then shared it between two people which is allowed...

Also I should note that users are a useful concept for businesses so that they can manage usage and things like access control easily but for me I didn't need that so a single user was sufficient.

That's a different scenario. All you can eat buffets people will turn up and all eat a similar amount. At a company, multiple people will want to logon and look but fundamentally the only entity that needs to download is the business. Each staff member won't each be downloading similar numbers of photos. It makes more sense just to have multiple access points to one fixed account.