On the other hand, a pasta sauce would generally retain chunks of tomato, use less (or even no) vinegar, salt or sugar per unit volume; and it would be applied to non-greasy pasta in much larger volumes :)

Historically, ketchup was a class of condiments that all had a lot of umami like fish sauces and oyster sauces. Over time, different ketchups were invented, one of which was tomato ketchup. Its popularity grew, and the other ketchups were forgotten, so these days ketchup is synonymous with tomato ketchup.

What you've described is just called tomato sauce in my part of the world (Pacific Islands, Australia, New Zealand). So what we call tomato sauce, you call ketchup.

EDIT: I found this https://www.atlasobscura.com/articles/heinz-ketchup-australi...

Interesting. Do you have a different word for the tomato based sauce made from fresh or canned tomatoes often used on pizzas and pasta?

Tomato Sauce and Ketchup aren't quite the same thing here - ketchup is probably stronger and thicker, but they are used the same way.

Incidentally, the best tomato sauce is whatever magical sauce they use on the hot-dogs at A&P shows.

For the confused people in the audience: There is a product, in Australia, much like ketchup, marketed as “tomato sauce”. Yes, people make pasta sauce with it. Yes, pasta sauce made from scratch is better. It’s not so dissimilar from ketchup, just a little less vinegary.

With tomato sauce? Really?

I know about ketchup and 'tomato sauce' as being essentially the same condiment, used on a hot dog or what have you.

I've never heard of someone using actual ketchup/tomato sauce condiment as a pasta sauce. Literal spaghetti and sauce (that we all ate as kids, don't deny it) from a can would taste better.

Apparently it's a thing here in Thailand, but given how most Thai places in western countries treat Thai food, Im not sure I have much place to tell them they're doing it wrong.

[1] The Japanese however, might. https://www.japanesecooking101.com/spaghetti-neapolitan/

I’ve tasted variants of this. It isn’t for me, but I never cared for ketchup.

https://en.wikipedia.org/wiki/Naporitan

The Japanese can only blame themselves for the ketchup-flavored popsicles though:

https://soranews24.com/2014/03/27/we-drink-japans-spaghetti-...