Who cares about 10k lolz, where do you think I got that number, it's from the page you screenshotted. Can't use it for margin if it's in a bank account. Don't want USD exposure since I don't live in the US.
Apparently It's not possible to respond to this topic w/o people getting pedantic about edge cases of the cash thresholds. Boring. Tell me something I can't look up with 2 clicks from IB's front page.
You want free lunch! Can't get positive interests on EUR without risk. The risk-free rate is negative. End of the story!
I was explaining to you why someone might keep "hundreds K of idle EUR cash" or other forms of EUR exposure in their account.