Is this really a thing in the US? In Italy (and AFAIK in most of Europe) wedding rings are normally plain gold (rarely white or red gold, or platinum) bands. Engagement rings do have a stone, but they are not worn every day.
Good lord, people do this? People spend ten thousand dollars on a ring? Fuck. When we got engaged, we shopped together and I bought her a black opal ring. Diamond was never on the menu, so I never even looked at their prices. I knew diamonds were expensive, but I had no idea the extent to which people were getting suckered.
No, of course not - why would you think that? Those 'high priced' rings are like the wax fruit in a greengrocer, or plastic lobsters at the fishmongers - just there for show...!
Back in the real world, people can actually spend hundreds of thousands, even millions, on jewelry.
In Sweden at least it seems to be quite common to wear both rings. However it also seems to be more common to have inset stones, rather than one that sticks out. I've also seen several people who buy the engagement ring and wedding band together as a matching set to make sure they work together. (something which to me always felt rather presumptuous)