I can guarantee you that pretty much everything that's in ketchup is in barbecue sauces at the very least. It's primarily tomatoes, vinegar and sugar. The spices in it are things like onion powder, garlic powder, salt, celery salt, black pepper, mustard powder, and cloves which are going to be pretty common in most things. Celery Salt helping to act as a preservative. Salt, pepper, onion powder and garlic powder are literally in everything. Mustard powder is pretty ubiquitous in barbecue sauces, but is probably missing in other sauces. Clove is the one that "might" be absent so maybe go sniff some cloves see if that's it.
Personally I wouldn't say ketchup smells overly pleasant and I like ketchup, but I think barbecue sauces smell worse, but nothing reeks worse than beef base IMO. The smell is mostly going to come from the vinegar and tomatoes in ketchup though and vinegar is generally displeasing to the olfactory sense (I'd say tomatoes stink to me too though).
Not to try to burst your bubble though, but most store bought barbecue sauces use ketchup as their "tomato base".