it has more to do when you buy a supplement that has those items in it. L-C is more expensive than M-A so a lot of times you will see that the ratio is much smaller. So say a company markets a product that has those two ingredients in its "proprietary blend." Chances are they put SOME L-C in it, but who really knows since they don't have to label specific amounts. When you see something is Bonded Citrulline, you know that it's going to be 2 parts L-C, 1 Part M-A. If that makes sense.
I could technically make my own supplement and put 1g of L-C in it, and 5g of M-A in it and just write on the label "Proprietary Blend - 6 Grams." then list the ingredients of the blend. Someone may look at that and assume it's 4g L-C and 2g M-A, but it's not. So what I've done is essentially tricked people into thinking that they're getting a product that has a 2:1 ratio, but really doesn't. And since M-A is cheaper I just saved myself a bunch of money in production costs and can still sell it at a ridiculous price. Always gotta be careful with the whole proprietary blend thing.