This is not necessarily true at all colleges. Some require some sort of proficiency test (either the college’s own test, or sometimes AP or SAT subject or other external tests are allowed) to prove a certain level of proficiency if one wishes to fulfill the requirement without taking college courses. A few, like Yale, require course work even for those with relatively high levels of proficiency: http://yalecollege.yale.edu/foreign-language-requirement .
As a practical matter, Spanish may be more useful for a physician or pharmacist who interacts with patients who may include those whose Spanish is much better than their English (more common than those whose Latin is much better than their English).