If I go set up a company in Brazil, or anywhere else, and it's legal and all the fees are paid, then I'm not "fooling" anyone when I ask for a domain name there. if the registration rules permit an existing company to register domain names, or indeed to do any other business in Brazil, then why shouldn't people do it? After all, the same kind of thing is done routinely for trademarks, patents, mining claims, etc. etc. It's as old as the law.
This isn't for people who've set up a company in Brazil. It's for people who have no presence in Brazil (or whatever country) at all.
I've spent a lot of time in this area and never once have I seen a decent justification for restricting registration to residents only, businesses only, businesses with licenses only, businesses with an account with the local telecom only, people who pass a language test only, people who use a particular ISP only -- etc. etc.
So, if I understand you properly, we should just ignore any rules that we don't like? R's, John