Thanks for the info! I will continue to give him bones, then. Yeah, I know I can get bones cheaper elsewhere, however, I hate going from store to store to store to buy things and was in a hurry, so it was more of a convenience impulse buy after I couldn't find his usual expensive bully stix. Calculating it out, at least I found something cheaper than those!
Next time I'm at the grocery I'll look for the marrow bones, which brings me to my next question, what is a marrow bone? Just the femurs or are there other kinds? I am not very worried about him swallowing big pieces. He chews really well and even spits out pieces if they aren't chewed enough.