Someone i knew at goog got let go for not passing background check like months after start date. Just had empty desk one day with no explanation from management. Kinda bullshit if you ask me...
I once had a similar situation happen at a very large (150k+ employees) company. Security showed up and escorted one of our contractors out the door. It turned out he had worked for the company previously and stolen documents that he used to try to extort money from the company. When he was being brought in for this contract position he had changed the spelling of his name on the form and used a social security number for someone with that spelling. During the quick background check everything looked good but the discrepancies were discovered during the more in depth check a couple months later.
Either way, I agree with you - pretty BS.
The background check company called all of my previous employers. One former employer gave them incorrect dates for my employment, contradicting what I put on the form. I never heard anything about it from Google.