Cracking eggs is a lengthy process? You've got to be kidding.
Seriously. The whole convenience food thing is getting out of control. Cracking and separating your eggs takes less than 30 seconds. Unless you are eating the whole dozen. You can also do it the night before.
Why not just eat the whole egg? The yolk is very nutritous in fact much more nutritious than the whites. If it is because of the cholestrol thing that has recently been shown to be incorrect, they type found in yolks is not the type that contributes to heart disease.
I buy these from leshop regularly - I bake regularly, using more whites than yolks, and I find it very wasteful to bin a load of yolks when making meringue etc (or on the occasion I make custards, to bin a load of whites).
For anyone else looking (found this thread while searching for egg whites), LeShop does not seem to carry them anymore but I found them in online sport shops ( example )