1) I don't know what country you're from, but in America here is how it works: In general, competitive colleges require at least two years of foreign language classes in high school. Stanford would like to see three or more years, and Harvard urges applicants to take four years.
When a college recommends "two or more" years of a language, they are clearly signaling that language study beyond two years would strengthen your application. No matter where you apply for college, a demonstrated proficiency in a second language will strengthen your application.
Students who have just the minimum can win admission if their applications demonstrate strengths in other areas. Some less competitive schools don't even have a high school language requirement and assume some students will simply study a language once they get to college.
If you score a 4 or 5 on an AP (advanced placement) language exam, most colleges will consider that evidence of adequate high school foreign language preparation (and you're likely to get course credit in college).
2) Foreign language requirements are originally a product of enlightenment era education curriculum and have been kept afloat with notions that in a globalizing economy candidates who can work internationally will garner higher wages and be more productive. This is true, to a degree, but wouldn't you rather work for a Swedish web design firm from your US based coffee shop?