I really have a problem with lakto-ovos using the well it's a bi-product let's not waste it. The long and short of it is that the leather usage is an integrated part of the meat industry, you can't have one without the other.
The biproduct-waste argument could be aplicated to any part of the animal really, or reverce it, we need the leather why not use the meat, it's a stupid circle argument, but why not eat the liver, it's just a bi product from meat production...
The long and short of it is, animals are not ours to use!
Something irrelevant about cavemen