[yalok]

I learned Bokmål Norwegian through my Norwegian friends, and they spoke and wrote to me in it consistently, while some of their patients would use heavy dialect that I didn’t understand at first and was shocked how different it sounded. Hva for noe - sounded as “Ka fo noka” from her mom, shouting through the house, to inquire on something…

[Tor3]

I think you meant "parents" not patients - I was a bit confused at first :-)

What happened to you is probably that your friends, for your sake, tried to "speak" Bokmål to you (Bokmål is a written, not normally spoken language), as in practice that's how you have to teach Norwegian to foreigners. You have to come up with something where the writing and the speech actually matches. Where my wife was taught they did it that way - a teacher explained to me that it was their only choice, even if it's awkward. And (as told to me by foreign co-workers who did that program) followed by a shock when they've learned "Norwegian" and find out that the people around them speak totally differently, with different grammar even!

So yes, I also spoke a kind of "bokmål"-rinsed Norwegian to my wife when we were just switching to speaking Norwegian. But now I don't. It was a bit weird (had to remember to change the word order now and then, in addition to vocabulary), but I got used to it. It's also a trap though, if you keep up "sanitizing" the language for too long the other party (the one who's learning Norwegian) will not learn enough real vocabulary and may way too long be unable to understand random old people from the district visiting town. Which is something you need to do if you're working in a shop, say.

[matsemann]

I'm from a dialect speaking part of Norway (Hallingdal), and my peers and I would speak like Oslo (so closer to bokmål) together. But they would always speak in dialect with teachers, their parents etc. My parents are foreigners, so I then never picked up on speaking the dialect myself. But it's still a shock to have a conversation with them, and how they suddenly switch when picking up the phone or whatever.

Not entirely sure why they switch. Was it to "be cool" with friends? Or to suck it a bit up to authority figures?

[Tor3]

I never change my dialect when I travel in Norway, for any reason, as long as the one I'm speaking to is native. But some people are extremely sensitive to how others speak, and may unconsciously (and some consciously) try to mimic the one they're speaking with. In the past though there was some discrimination going on. In Oslo you could find advertisements for apartments, for example, with the text "no northeners please". That's only sixty-seventy years back. People moving to Oslo from elsewhere would then try to change their dialect. Despicable times. Before my time though. There's nothing of that anymore, or, if there are any individuals around who actually thinks one dialect has more prestige than another.. the vast majority will ignore them, just as they ignore other morons (for lack of a better word)