Why would a girl ask a friend to tag along with plans?

Anonymous
been friends with this girl for a long time, she has a boyfriend who is also a friend of mine. a casual friendly plans for food, or maybe a movie, she always asks a friend to come along (not a big deal) it does make it more fun with three, but it would also be nice to catch up alone. only time we have really been alone is taking day trips to go snowboarding. yet other plans a friend usually comes. so why would a girl invite a friend to join all the time on any plans, even tho we have been friends for a long time?
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+1 y
well its def not a setup, cause the friends have their own boyfriends, and I have never made a move or shown stronger interest than just a friend, and I have never seen any signs of a stronger interest towards myself either.
Why would a girl ask a friend to tag along with plans?
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