I've lived in Italy and they have them there, too. They say hay or pasture with foxtail is worthless. They also believe it causes the same sores down towards the stomach.
Apparently when the hay is made fairly early, the seeds are not dangerous yet, because they're still soft.
And, I used to find them everywhere stuck in my clothes, all the way to the underwear....even after washing.....
If present in pasture keeping them from seeding through mowing make them die out eventually.