I must be the luckiest guy, cause I've hunted the sandhills from Oneil to west of Valentine for 30 years and never booted a dog. They quickly learn to avoid cactus and I only find significant sand burrs in disturbed soil and I've never found many grouse where there are a lot of sand burrs. But then I've never seen a rattle snake or porcupine either for that matter.
If your dog tries to throw off his boots, just walk off and leave him. When he sees you going hunting without him, he'll forget about the boots.