Reaching out to admissions representatives in person at an event or by email is a great opportunity to add give them insight into your personality, values and goals through the questions that you ask. It is also a great way to demonstrate your interest in the college; an increasingly important way you can tip the scales in admissions decisions (colleges want to pick candidates who will pick them).
If you have a rigorous course load, stellar test scores, and a packed activity list you are in pretty good shape. However, many others are in your same boat and YOU have to stand out even more.
Admissions officers want to see beyond your academic and personal resume to understand who you are. More specifically: how will you enhance the campus and ultimately become an influential alumnus? If your application can showcase that – then you are in really great shape!