I've been in situations before, with other vehicles, where I replaced bolts all the time, for the reasons explained here, Mike just above. There's been some rather detailed analysis performed with some rather sophisticated equipment, that can be quite compelling actually.
Given that many are replacing the LBJ for safety reasons, and I'm now pondering such sooner as opposed to later, I'd be inclined to replace the bolts too. They are not exactly price prohibitive...
That all said, there have been times in the past where I have not replaced bolts that I otherwise would have because there were concerns about the newer replacements being produced. I forgot the ride, but the bolt purchased at the dealership was markedly lighter (and was, per scales), just felt less substantial than the original one.
A few were sacrificed or torqued to failure (snapped), and they did so consistently with less torque than the original bolt's failure point. Rather eye-opening and made a few us reconsider the blind practice of bolt replacement. Just a caveat...