Bourbon only requires a glass.
Personally, I've only seen liter bottles of W12 at Spec's in the last couple of years. Maybe I wasn't looking hard enough back then. Months ago, liters were the last format I saw, buying the last case , before W12 seemed to completely dissappear from the shelves. Now that they're restocking, I'm only seeing 750s and 1.75Ls. Not sure if the liters were old stock or are normally just available to bars and restaurants?
Then I stop by Spec's today and see liter bottles of W12 stocked again, first of which I've seen without the embossed wheat symbol.