1. A buyer truly believes that Gox death would mean Bitcoin death or stagnation for 5-10 years and, thus, his own coins would be worthless anyway.
2. A buyer believes he can make more than 770k BTC he'd have to pay back customers.
However, I don't really think they've lost that much. It is simply insane. I don't believe anyone can be that incompetent, especially after reading Mark's 2012 message about security here: https://bitcointalk.org/index.php?topic=23938.msg1177353#msg...
Update. Rumor on twitter about the acquisition: https://twitter.com/paulbuitink/status/438428157948219392
Nor would the previous owner's past be reason for someone not to trust the current owner of the brand. You wouldn't stop trusting Bitstamp or BTC-e if they happened to buy the MtGox domain. Nor would someone reading an old NY Times article stop to research the past owner's history.
The grand vision of Coinbase isn't to capture as much of the Bitcoin speculation market as possible, it's to capture as much of the e-commerce payment market as possible by offering lower transaction fees and eliminating chargeback risk for merchants. If, for example, they took over the MtGox domain, and that helped stabilize Bitcoin and continue its push towards the mainstream, then "snitko's and 0.02% of our target market's image of us is tained by Gox's past" is probably a good tradeoff.
Their value has been totally demolished in the eyes of their current customers and in the eyes of all potential customers. It's so bad that it has set back Bitcoin's adoption by months, if not years. The freaking Wall Street Journal published articles about it!
If this is not a case of fraud, then it is one of the worst and most poorly managed acquisitions in history.
The large number of AML/KYC verified accounts could be valuable to other exchanges.