I suppose it depends on whether you are dealing with Catalans or the rest of the world in your daily life as to whether or not you learn the language.  Spanish, of course is one of the major spoken languages in the world and well worth learning.

The right to a translator is enshrined in EU law which is one of the things that seems to piss off the British when they are expected to provide translators in Polish or Romanian but they are happy to take advantage of it when they get pissed up and arrested in Spain.

Again my point all along has been that the British are just arrogant in assuming that everyone will speak their language when they aren't tolerant of people who haven't mastered English when living in the UK.  Double standards.