I assume you've tripped up on your measurements somewhere, because 4 ml would be a very sad dram. A spirit measure in the UK is 25 ml, so you get 28 of those out of a 700 ml bottle for $7,000 at that bar.

Edit: upon looking it up, apparently a dram actually is 4 ml in America? In Scotland that's just the word for a glass of whisky, assumed to be an approximate "one drink" rather than an actual specification of volume. If you offered someone a dram and poured them 4 ml here, they'd think you were the stingiest person since Ebenezer Scrooge

However bars mark drinks up like mad, and they will absolutely do so on extremely premium drinks because the only people buying those are people who do not care how much it costs. If you take $3 for a shot of a basic vodka, that's $84 for the bottle, and there's absolutely no way you'd pay $84 for that same bottle in a supermarket.

You definitely could spend seven grand on a 40 year old bottle of whisky if you went looking for one. This specific bottle is 51 years, but it's commanding this price because it's a very rare special edition from a big and popular distillery