I've heard of this out here. Isis' only fetish is sleeping.

Be warned. Asking "why", like I still do today, only results in a deeply
frustrating sense of bewilderment. Just now I was wondering "why" Isis loves
to have her head petted. Why are head butts so popular amongst felines? Why
don't they prefer having their ears stratched over every other possible
pleasure? Why did she sit last night gazing at the little plastic jug ring
before pouncing? Is there some hidden magic aura around that little ring? Is
it the little plastic nubs on the ring that make it so attractive? Do the
plastic jug makers do it on purpose?

I have to stop now. It's time for my meds.

Mike in Illinois

My cat loves to *sleep* on plastic bags, so I can sympathsize!

One of our cats will lick plastic bags - it's usually when she's hungry.

all my cats have done this, i dont know why but it appears to be Grizzy's
favourite occupation after playing ball. it has never done them any harm so
i would just let her do it. I do make sure handles have been ripped so they
cant get it round their neck.

Cati