Membership at Gym? 18+?

So I was thinking of signing up for this fancy gym with my other friends but we just found out that you have to be 18 and older to become a member. I just recently turned 17 and the rest of my friends are 17 and 16. So before requesting a membership consultation, we were like wondering if our parents could sign up to become member and we'd just use their key cards to access the gym. I mean all our parents are in shape and have their memberships at other gyms but we wanna go together at this specific one. Do you think they'd allow that?