OK, let's be fair. There are some pretty awesome commercial barbecue sauces for sale. Arthur Bryant's comes to mind. And that special Alabama blend given to me by a good old boy.
But you're not going to find them at Safeway. Megamarkets carry sugary glop, and the sugar is high-fructose corn shit. (Shut my mouth!) They are oddly flavored with artificial smoke, bourbon, peaches, and all manner of stuff that doesn't belong in there.
Don't even get me started on ketchup.
I've always liked brewing my own barbecue sauce, and as recently as the most recent decade ago, I squirted ketchup into the mess for a sweet, tomatoey tang.
Ugh. All you taste is oil of clove.
I don't even have ketchup in my house anymore. I have homemade tomato sauce, frozen in little plastic bags.
So. How I do it: Marinate your pork spareribs in a good home-concocted marinade. (We are talking about ribs, right?) Then save the marinade, boil it down (to eliminate possible pathogens, to concentrate it, and to let the scum rise to be skimmed). At this point you should add tomato sauce or even tomato paste (I use both). A spoonful of honey. Tinker with the flavors. No mustard. I don't even bother with garlic. Let it cook into a beautiful, soupy slop.
You will love it.
Do not apply the barbecue sauce to the ribs until after they're cooked. You don't want blackened, bitter flakes. Ew. Just cook the meat lovingly, and then pass the sauce at the table.
Here's a rough approximation of my marinade: Equal portions of distilled white vinegar (hey, we're going the hick route, aren't we?) and — ohgod, I'm embarrassing myself here — vermouth. I used a highly botanical vermouth, and it adds tons of flavor. A little tomato sauce, but not too much because the sugars will burn in the grill (but meat loves to be tenderized in tomato). A terrific sploosh of Tapatío hot sauce (which reminds me of the Arthur Bryant's sauce). A drizzle of Worcestershire sauce, and an equal drizzle of soy sauce. Put this in a sealable plastic bag with the ribs, overnight in the fridge.
Next day, pull out the meat, save the juice, and follow the above guidelines.
UPDATE: There is some discussion in the comments about whether this is a safe method for making sauce. I stand by my recipe, but I totally understand the concern. Use your discretion.