I agree that learning pleasantries in the local language is absolutely required for English speakers. But IMO if the value of learning common phrases, particularly questions, is dubious unless you are really trying to master the language.

Watch a boatload of tourists with their "dos cervesas por favor" Spanish, for example. When the waiter replies "Qué tipo de cerveza te gustaría?" their faces go blank. The conversation then repeats itself in English, which it should have been in to begin with. No use in pretending that one party is anything other than monolingual.