If they are using this quilt on their bed chances are that the cat is sleeping with them pawing the quilt of a night time. It happens to my quilt (made by me) all the time. A quick run through the washer and drier "removes" the holes.
If the quilt is already showing wear after a year and a half chances are there is more of a problem with the fabric then the way they are treating the quilt, unless they use it as a car mat in the garage or driveway!
Now I will say that I don't think there is an even medium here. people either want their gifted quilts to be put up and never used, or they want them to be used until there is nothing left of them. For those that do not want a quilt used maybe adding a hanging sleeve to the quilted gift would be a great idea. This way the gift recipient knows that it is NOT to be used.
Good luck at the show!