They'll look for external options whether they're paid lessons somewhere, English-related events, or online chances to talk to native speakers. Many will also go on to look for jobs in companies that involve English.

It's also worth noting that most public schools have (short) study abroad programs that will allow excellent students to apply for a few weeks in Australia or New Zealand as well.

One other interesting part of the uniformity is that perhaps because of the English focus, there's no real exposure to other foreign languages in public schools before the high school level (and sometimes not even then). Whereas in the US, I think most people have the option to study something from middle school or junior high.

I'm excluding Mandarin from this discussion, which is sometimes touched on superficially in Classical Japanese.