Are you talking about a DH renewal fee?
The only way I can picture that being possible would be if someone registered a domain, then entered ns1/ns2/ns3.dreamhost.com as the nameservers... but didn't have a hosting account here.
In that case, it's not hijacking... it's someone giving you a free domain!
But what are the odds of that? You typo your own domain and end up entering a name that is not only valid, but is also pointed at your host with no other active account claiming it.
I'm adding Google to my account... I always wanted that site.
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