Lets say student A plays soccer and student B plays racquet ball. They both play at the same level, attend national tournaments, etc. Would student B be more intriguing to AOs because soccer is kind of a dime a dozen sport and a sport like racquetball (or badminton, or archery, etc.) is more unique?
Maybe if you were an Iditarod dog sled racer it would pique some interest, but badminton/racquetball aren’t all that unique.
A hook is something the school needs, so if it has a soccer team and the coach wants to recruit you, that’s the hook! No amount of racquet ball achievement will get you recruited for a team the school doesn’t have. Do no, thAt Is NOT A hook.
With that said, a very high level of achievement in anything will make your application stand out, hopefully in memorable way. I can envision mention of the "unusual " achievement in the annual “here’s who we welcomed to campus” article in the alumni magazine. So yes, it could help in the process - potentially a lot. - but it is not a hook.
Ditto what @gardenstategal said. A hook is something that makes you needed/desired by the school. DO they need a cello player and you are a top cellist? Etc. If you aren’t a recruited soccer player for some school team, and they dont (likely) have/need a racquetball player, they aren’t. hooks.
Olympic athlete might be, even if not recruited.
Since the advent of the internet, there probably aren’t a whole lot of “unusual” sports. Whatever it is you play, someone who plays it much better has access to the same info on the same schools you do.
MODERATOR’S NOTE:
Let’s leave the College Admissions forum for actual questions based in reality. “Let’s say” is a hypothetical, so is more appropriate for the cafe. Thread moved.
Unless you are a recruited athlete for either soccer or racquetball, colleges will consider either just another EC. Use it on your application along with other EC’s to show that you are well rounded.