Maybe, but it would have been equally as instant to just set all domains as "WhoisGuard purchased until the year 3000" in the database, and much more user-friendly.
If you're registering as a business rather than an individual it looks dodgy to have a whois privacy record instead of your business details. Not necessarily a deal breaker but definitely a single red flag
Because whois, along with the many people who scrape it, provide a public record of my domain ownership. With privacy protection it is a lot harder to prove ownership if the registrar makes a balls up.