The point is that by using an SMS as 2fa, is placing much of your security in underpaid cell phone store workers.
Neither they are here (in EU), but nobody is going to talk to you unless you provide an ID anyway. Asking for ID doesn't seem too hard, even for non-trained personnel. You don't have to be a detective to match name/code on ID with the name/code on account.
It may happen with certain large scale scams involving organized crime, but not for small amounts; it simply doesn't show up in practice. What does happen is use of real IDs that are stolen (or bought from homeless people), but most places that have some risks have access to registries where they can verify if the ID has been reported as stolen.
I mean, as soon word would get out that some company allows that, they'd be exploited for free stuff in large amounts; all of the obvious loopholes have been tried and plugged in the last couple decades. USA has the problems only because they treat it as "stolen identity" instead of "someone defrauded a company with fake ID", and don't have proper universal IDs and try to make do with a mishmash of driver licences, names, addresses, SSNs, etc.
How that can happen? When I visit my cell provider's store, nobody is going to talk about any account details while you haven't provided a government issued ID to prove that you are an account holder. Sure, it's not 100% bulletproof method, but if somebody went a great lengths to counterfeit my ID, phone number is the least of my worries then. I assume, this happened in USA, so is ID check so unpopular there or it's easily circumvented somehow?