I got what you meant, and in a way 'our people' (the Dutch) are very much alike. We are fairly direct and just thank you ('bedankt' in Dutch) is enough to thank someone. You're welcome (alsjeblieft) is enough when you give something.

I think the alternative motives also play a role here. I just think it shouldn't be that way.

Interesting take you've got here.

You're very welcome; and yes, you may. I'm from the Netherlands.

How about you, kind stranger?

Say please, if you'd like something. Thank you, if someone went out of their way to help you. You're welcome, if you helped someone out. Excuse me / I'm sorry if you don't want to be rude and want to ask for something. May I help you? to offer your service. I would like / may I please have, if you want something.

Not a native speaker either, but I've found this to be helpful on vacation or when directly approaching someone who I don't personally know

When responding to advice, say "you're right" instead of "i know." It shows that you're actually listening to someone, that you care about what they say, and give them credit for trying to help.

You'd be surprised. I used this trick in a job I had a lot of times.