This "loophole" is necessary to allow certain usecases not to need a banner or opt-in at all. E.g. If I want to buy something online, the shop has to know my adress to ship me something. It shouldn't have to ask to use it for that usecase. Otoh, if it does not ship me anything and still asks me for an address, that would not be legitimate interest anymore, except it can argue for it (e.g. needs the adress for the invoice).

I would argue that this loophole is for conveniency and was not a hot topic anywhere. How it used now however is a different thing.