I'm still reading the chapter about bottling in A Bottle of Guinness Please by David Hughes.
In the 1980's "smaller bottlers could not make money out of NRB's [Non-Returnable Bottles] and dwindled away...In the EU, all countries get Guinness Original 4.2% ABV and most are NRB except for Germany where recycling is important and Belgium, where John Martin gets Special Export 8% ABV."
The idea behind returnable bottles is that the purchase price includes a deposit which you get back when you take your empties back to where you bought them. They are then returned to the bottler who washes and reuses them, reimbursing the retailer for all the deposits they've paid out. I just about remember R. White's returnable glass lemonade bottles from the 1970's. It's clearly a greener method than plastic disposable bottles which are though cheaper to make than glass bottles, especially the returnable ones that are slightly thicker.
The stuff about returnable and non-returnable bottles reminded me of an episode in one of my favourite books, My Brother Brendan by Dominic Behan. Behan and his brother are drinking in McDaid's - a Dublin pub that, like many tourists, I've also drunk in - before heading off to a party with crates of bottled Guinness.
"'Mr McDaid charged you on each bottle no doubt?'
Brendan said, 'Three shillin's on every sacred dozen.'
"'How nice,' sang Bertie, 'only last week I took back a brigade of empties to that horrid Murphy's and the dreadful man merely said, "Thank you very much, sir, it's not often people bring them back on their own." I'm bloody certain it's not. Three jangling miles to the accompaniment of ragged children asking if I was giving balloons for rags."