To me, "jug" is an old-fashioned word encountered in song lyrics and books, and "ewer" is a crossword puzzle word. I gather that they are in common use in Ireland? Pitcher that!

Jug is very much in use here and always has been as far as I know. It's quite common to ask for a jug of water in a restaurant and a milk jug is to be found on all breakfast tables.

A ewer is less common. Until just after the Second World War it was used (with a bowl) for washing. Any older generation people who have kept theirs use them for watering plants and the like.

Pail and pitcher both have L -> F -> ME histories, and I'm wondering if they are two words which were in established use by all English speakers a few hundred years ago but which the North Americans held to whilst the rest of the English speakers came to favor other terms?

There is mention in Shakespeare's works of a Toby jug - a grotesque form of designed pottery beer mug in the shape of a seated man - and this seems to have taken England - if not the rest of Britain and Ireland - by storm. The US was spared from this form of art and chose to adopt the pitcher instead.

A number of US theme restaurants have sprung up around Europe and a couple have landed here (with little success, I may add). One possible reason for their demise may be down to their selling quart pitchers of beer for a fixed price.

1) "What's a quart?" is the first thing that will be asked by the patrons.
2) "How many pints is that?" is the second.
3) "That's bleedin' robbery" is the blunt comment when realising that the price/pint is extortionate.
And finally (bringing Irish logic into the fold)
4) "Bring us it in a jug next time. That'll be bigger!".