How about we call it what it is. Advertising. However you frame it, it's advertising. Is it useful? Who cares. It's advertising. Order a pizza using the app and your telco gets paid. Twice. Being able to remove Apple's built in apps is besides the point. Yes, it's mildly irritating that this can't be done, but it's not the same thing. Pretending otherwise is disingenuous.

So if a site shows ads for its sister sites it's less intrusive then an ad for a pizza?

What has that got to do with anything? We are talking about an app! Not a blockable ad on a webpage FFS.