Some of the top selling have strong grocery store sales and reps that have been promoting them to the buyers of chain stores.
If you have one product that sells,most will get as many other associated products as they can find and slap their label on it.
As long as you have the website running,the ads paid for,the sales rep in the field,you might as well pick up additional sales dollars.
If you wish to have shelf space at Target for regional sales,your rep pays them a couple hundred G s and then the chain will market it.
This is naturally common thru other chains.
It is also common to go to a food chemistry lab and pay them to break down a great selling product and then you market it under your name.
Thus, a major bleach company may be making and selling sauces.
Naturally,if you win Team of the Year,you better get a bunch of labels and your smiling face on them quickly.A sauce company and spice company can give you all the products you wish to claim,as fast as you can get some labels printed.
Doesn't mean that those products can't be tweaked to fit your own flavor profile.
I see 7,or 8,including David's, that actually are used by good cooks and have a legitimate place in building flavor profiles.They have been recognized for quite awhile.
I see four on there that are used a lot thru the comp world,and never see a grocery store.