I think there are a few potential variables in your bales of ryegrass hay. The first is how mature the ryegrass was when it was cut and baled. If it is full of mature seed heads, then the stem has grown to maturity and can be "stemmy". The ability to bend the stem and have it snap may be due to the moisture content in the hay. Really dry things snap, and stems with a minor moisture content will bend. Another potential variable is if it was a pure stand of ryegrass or if there were other things growing alongside the ryegrass that may be contributing to the stemmy appearance of the hay. Ryegrass can make really excellent hay if it is cut and baled just before or right when it goes to boot stage, which is the term for when the seed head begins to develop. Most often, farmers don't get to cut hay when they want to or when grasses are at their peak, but rather only when the rain stops long enough to get everything cut, raked, baled and stored.
Also is it true the bearded grass will hurt the animal's mouths and cause them to get infections or is that a myth?
It depends. And it depends on two things- the type of seed head and the animal. Horses can get hay blister from eating certain grasses that have awns, which are stiff bristly parts of seed heads, such as foxtail grass and barley for examples, and the same hay fed to cows or goats may not cause any problems in them. My cows really enjoy grazing foxtail grass in the late summer and the seed heads don't bother them but apparently do cause problems in horses. I have what my neighbor calls a wild barley which grows in the region in the spring and has awns on the seed heads and my cows won't touch it, and I don't blame them. The seeds get in my boots and are really pokey and I find myself stopping often to take off one or both boots to pull those bristly seeds out of my socks.