Use them all the time in midwest whitetail and turkey hunting. Ranks up there with my knife and bow. I determine size of deer, do I want to call them in, get ready etc. I have ambushed tons of turkeys- seeing that slight head in the brush before they see you is critical.
Western hunting optics are essential. You could hunt without them, but spending hours glassing is FAR more productive than wearing out the legs, spooking everything, and hoping you stumble into them.
8 (or 10) x 42 in the best glass you can afford seem to be the good all-around optic. Some type of harness (simple bino buddy to Alaska Creations, etc) that holds them close to the chest works great for all types of hunting- even in the treestand.
Of course- western hunting does open an entire optic discussion; scope, binocs, tripod, head etc. Reading and listening to the newer podcast world on such issues is a great education. Be prepared to work some overtime or a part-time job.
Dan in KS