Yup, birds cause damage.
Been there, done that.
Toys will cause damage.
Not had that yet.
How many aircraft have been brought down by a single bird in the last decade worldwide?
How many birds are there?
Just because something will inevitably cause accidents is not an excuse to ban it.
If we went down that route all PPL pilots would be grounded.
All motorbikes.
All radio controlled aircraft.
Boomerangs.
Frisbees.
Cricket balls.
the list is endless
The only thing to do is assess the realistic risk.
The simple fact is that despite vast numbers of these things having been bought in the last couple of years and lot of general worrying, the worst anyone can come up with is one collision with a Cessna, no damage and a dent in a de-icing boot.