I learned English from TV (the TV where I lived was subtitled not overdubbed), games, and reading books. I also I have a better than average understanding of Italian from (I assume) watching Italian TV without subtitles as a kid. I can understand most Italian (90%) but cannot string together a single phrase. My native language is Romanian and as such is 70% percent similar to Italian. However, I know a lot of people who do not understand Italian even though they speak Romanian as a native language. In English I am very fluent - better than the average native speaker from test scores and interaction with native speakers.
So I think TV, books, games, etc do help even in the absence of native speakers.