I think maybe they are just frightening you? Anyway did you read properly before signing anything? Usually they wont give refund one. my friend also got cheated by a beauty centre once. She also purchase a coupon from Groupon and then went down there for trial session but then the trial session was nothing described in the web. I guess we have to be very careful with this kind of thing. If you really dont want the package, maybe you can go CASE and seek advise?
For me, i will usually go this kind of beauty centre through friend's or family's recommendation.