BA offer complimentary alcohol in all classes on all routes short and long haul - and unlike some other carriers, it is not limited to 'one alcoholic beverage with your meal' - crew will provide other drinks on request throughout the flight (obviously at their discretion if you are getting blind drunk

IB Europe flights in economy are BOB - so no free drinks there. I would imagine that their long-haul product has at least some alcohol service included - most of the European airlines offer something, if only limited to beer and wine.

One of the BA crew once (a few years ago) charmed me with his response to my request for another drink on a SEA-LHR flight in Y - "of course - the bar never closes on BA!"

Shuttle