Thats the law that says you have to display a price list - might there be a separate piece of legislation regarding quantities? Of course if it says nothing at all about quantities - you cant find something that isnt there. I had a quick check around and didnt find anything.
The only thing i did find was in the piece you quoted above - which specifically says you have to isplay the prices for specific measurements (e.g. 568ml of stout, 35.5ml of whiskey)
[quote:15olq5s3]4. (1) Subject to the provisions of this Article, every person who carries on in the State in any premises the business of selling intoxicating liquor by retail for consumption on the premises shall display a notice specifying—
(a) the price per pint or 568 millilitres charged at the premises or at that part of the premises, as the case may be, for at least one kind of draught stout,
(b) the price per pint or 568 millilitres charged at the premises or at that part of the premises, as the case may be, for at least one kind of draught ale,
(c) the price per pint or 568 millilitres charged at the premises or at that part of the premises, as the case may be, for at least one kind of draught lager,
(d) the price per pint or 568 millilitres charged at the premises or at that part of the premises, as the case may be, for at least one kind of draught cider,
(e) the price per bottle charged at the premises or at that part of the premises, as the case may be, for at least one kind of stout in bottles of a capacity of 330 millilitres,
(f) the price per bottle charged at the premises or at that part of the premises, as the case may be, for at least one kind of ale in bottles of a capacity of 330 millilitres,
(g) the price per bottle charged at the premises or at that part of the premises, as the case may be, for at least one kind of lager in bottles of a capacity of 330 millilitres,
(h) the price per bottle charged at the premises or at that part of the premises, as the case may be, for at least one kind of cider in bottles of a capacity of 330 millilitres,
(i) the price per 35.5 millilitres charged at the premises or at that part of the premises, as the case may be, for at least one kind of whiskey,[/quote:15olq5s3]
I didnt see anything which said you are bound to sell in those measurements though.