What is a fake google bot

Googlebot is what Google sends out to crawl web content for indexing in their search engine. Googlebots use a specific user agent to identify themselves as being from Google. Fake Googlebots try to impersonate the real thing. Why is this bad? Everyone wants their site indexed by Google so allowing real Googlebots to visit a site is required to make it happen. By impersonating a Googlebot, an impostor can use the special treatment and access we grant real Googlebots against us. Fake Googlebots can steal content and inject spam into sites.

Hope that helps explain it.
-Brian