It only takes two to make value go through the roof, assuming you were ******* at auction. If someone is willing to spend $9,500 hundred for it and someone else $10,000, it'll sell to the higher bidder - even if perceived market value was $35 and 100 bidders were only willing to go up to $35.
Why would one of those two bidders be willing to pay so much? Perhaps one has a spouse who drinks Seagram's VO, and they were married in 1960 and they want it as a golden anniversary gift. Perhaps the other is buying for their father who was born in 1960. You get the idea - rationality is out for the rest of the market but not those two bidders. $9,500 & $10,000 is rational to them.
That said, the main reasons the bottle could be more valuable is because of its known bottling date (not the age of the whisky), the rarity that one just cannot go out and find a Seagram's VO bottling of this date easily (since most of them have been consumed), the producer has changed hands and/or is defunct, the label and packaging has changed or has particular significance to collectors and lovers of Seagram's VO.
You could look at it the same way collectors of baseball cards see cards. They're not concerned about the bubble gum or tobacco but the rarity of the card, the history of the player, the age, condition of the card... A hall of famer's rookie card will always have more valuable than a journeyman player who has a few cups of coffee with a few different organizations. Especially so if half as many of the hall of famer's rookie card was printed as the journeyman's.
Seagram's VO is a mass-produced product with little value for rarity beyond its retail price, true. But a run of the mill bottle can become collectible and valuable because of some strange circumstances. Like I said to start, depending on the marketplace, it only takes two buyers (and sometimes just one) to take the value to unprecedented heights.