But they are there just like we said they would be. They aren't going to hit you with every single thing that they can do. That installer is targeted at your average Joe blow users that doesn't even know what a bookmark is, let alone the definition of some foreign sound work like 'import' that they have only ever seen applied to cars and beer.

For years, installers have asked such questions, the frame of reference which is built over the years contains these questions to appear in the installation procedure. Hiding them reduces the user's control over their own computer.
It doesn't matter whether Joe Blow understands the questions, he will click through the default anyway. But hiding them behind a button hurts those who know how to answer the questions. And Joe Blow isn't using Opera, he uses whatever comes with his device, so targeting them with the installer is shooting the wrong target...

Certainly an option that takes over passwords and logged in sessions should be clearly visible. The option doesn't even clearly state what it's full capabilities are. With all my experience as an IT professional (decades), it wasn't even clear to me during the reinstall that the option would not only import passwords but also sessions and keeps doing that during use.
What also isn't clear to me, is that someone thought this was a good idea, and even less why someone tries to defend such obvious UX design error.

I do not think it means what you think it means. Opera never sees the contends of your password file. How is it a privacy violation if the only person to ever view it is you? Can you violate your own privacy?

Most computers have more than one user, so it may violate privacy because Opera is automatically logged into a website to which someone was logged in via another browser.

You just made two contrary statements. Was Opera effecting what was going on in Firefox or not? Seeing as how they are completely unrelated problems I don't see how being logged in to a pertiulare website in Firefox would have any effect on Opera or vise versa.

No it isn't contrary. I'll try to clarify:
I was logged into one account in firefox, and when I opened Opera, I was logged into that same account. I then logged out in Opera. Because being logged in on that site in Opera despite I never used Opera before raised already some suspicion with me of what was going on, I refreshed the site in Firefox. And that showed me as logged out on that site while I didn't log out in Firefox, only in Opera.
I of course tested further and logged in and out with various scenarios.

Some websites only allow one login per identity. That is, if you log in with a different browser or device, any other browsers get logged out.

I know, but this particular site allows multiple logins per identity and multiple identities logged in simultaneously from one computer.
It's also not only logging out, logging in via Opera logs you in in Firefox and vice versa.

It does ask you. There is a checkbox in the Opera installer that specifically asks if you want it to import stuff. This is why you should always pay attention when installing an application. You got some passwords imported, no big deal. I've seen malware installations that have resulted in complete data loss and the need to format the HD and reinstall the OS. All because someone left a box checked and when installing a completely legitimate program that had a bad piggyback program attached to it. Most of the time its middle of the road stuff. Java updaters has been recently either installing Google Chrome or setting your homepage to Yahoo and the latter has caught a number of our clients by surprise.

No, it doesn't ask you by default.
I had nearly the same issue as the topic starter, I wanted to be logged in 2 different accounts on one website. And I was sure that I didn't come across this question, or the question for the install location. So after your comment, I decided to uninstall completely and install again.
And not surprisingly, the questions are hidden behind an options button. This is very deceitful and very disappointing for a browser which has a better image for privacy than Google Chrome, but apparently that is undeserved.

Not only did Opera import the settings but they kept working cross-browser. When I logged out in Opera, I was on the same website logged out in Firefox. That is absolutely ridiculous behavior!
Even if the setting was not hidden, it should be an opt-in, not an opt-out. And it should be very clearly explained that it keeps working cross-browser.

A very very disappointing first impression with this browser...