pianistamediano
Forum Master
If there are 30 dancers, the organizer might recognize that there are 29 regulars and one guest. And I went to a large capital flagship milonga where the aim itself was in no way to integrate newcomers. Either you find dance partners - because you are attractive as a dance partner or because you took care for your network - or even not.
In the case of too many regulars and not enough guests/beginners, the organisers do make informed decisions and forego that tanda.
That latter case sounds very Darwinian, and it reminds me of the accounts I've heard about the BTE as a massive event.