You're right ! There isn't any benefit. Some people just feel insecure about themselves so trying to be like someone else makes them feel important. Wouldn't let it bother you.
What's the point of competing with someone? Some girl tries to compete with me on everything! I don't even do it back because there's nothing that benefits from it.
You'll find in life that sometimes people are competitive. Sometimes it can be a good thing.
My daughter's boyfriend skateboards. His best friend is really good. Because of his best friend he has become really good because he continuously competes with him to get better. Without his best friend competing with him he wouldn't be as good.
Growing up, I had friends who were competitive. Because of them I got better grades, and got better in sports.
My extended family is very competitive, for fun. I'll walk through the door for a visit, and they are out in the driveway playing ball. Loser has to do whatever is at stake. It could be buying ice cream for the winners, to wearing a silly shirt during dinner. They will play anything at any time. I could be sitting on the sidelines complaining about people being competitive or I could get in there and have some fun.
First a little competition never hurt anyone and in fact it really is healthy especially in always entertained competition in all areas of life. Competition at your age is a very good thing as youll need to learn how for your later life where youll always be in competition for something like a Husband/Wife, or BF/GF, jobs, promotions, even house buying so while you think its a small thing now, the day will come realize just how big a deal it is. Remember always find a way to win but win or lose, be a good sportsman here and learn well and youll be just fine
Annoying competitiveness is just part of the makeup of some personalities. Some of those people assume that everyone is competitive. Your friend isn't old enough yet to see firsthand that such benefit-free aggression damages some relationships.
So be polite, begin distancing yourself, smile. You are doing fine.
Ps. A book on etiquette for teens would give you more information on how to deal with difficult peers.
You are the smart one, there is no benefit. They must be jealous of you, and they will try and compete with you so they feel like they are at your level maybe. Good on you for seeing that there is no benefit. :)