Bank transfers are cheap and instant when both parties in the transaction have a working bank account, which means they had a residence where they could receive mail, which means they had government identification, etc.
For paper mails some shelters allow for picking up post and in some countries you can get the mail as "Poste Restante" (i.e. pick up at post office).
But yeah, if you’re not a citizen and don’t live in the EU it might be tricky (then again AFAIK bringing large amounts of cash from a third country is not that straightforward either).
What does this have to do with Dutch farmers, though?
This is as old as countries themselves. You must be intellectually dishonest to ignore these historically crucial patterns.