After reading the original post I have to say after a lifetime of shooting bows with the early years and sub par equipment to later years with more advanced..I never had any problems with vanes falling off. I have fletched arrows and also bought pre fletched at times over the years. It struck me his problems could have been the rest especially if the OP was new to archery and wasn't aware of a rest being out of adjustment or vanes improperly aligned to the rest. A problem like that would account for altered arrow flight and the skinning off of a vane. Just a thought.