The argument is quite weak when we discuss learning words in a foreign language. You learn that lunch is "almuerzo" in Spanish, but is it learning or just memorization/association? To me the lines are blurred, even at first sight of the word.
I used Anki myself to learn foreign languages and it is tremendously effective for words and short sentences too. I use it also for words in my mother tongue, and it made be much more articulate than I used to be.