Why specify passport data when registering a domain?

Question

Domain name market

What happens if I enter incorrect data?
Faced, who on personal experience?
Thanks in advance for your reply!
upd:
The moment is of particular interest: can the hoster transfer data to law enforcement agencies or does this require a court notice, etc.?

Answer 1

Then, that these are the rules of the national segment. Domains in the .ru zone are registered according to documents. The rest is optional.