My FIL, since he is too lazy to learn the proper Portuguese word, calls it the Fressinger (from the collocial verb use of fressen).

When I remember the mess it makes when you eat it, I think it's a proper nickname

I remember seeing a TV program about fishers collecting the percebes in Galicia....a damn dangerous job. I heard the price is in the range of 100 euros/kilo! Need to go to spain to enjoy it.

what's cavier?

It's the first (and only) dish my Portuguese OH cooked for me. He was so proud of it

I only managed half the sandwich though

OK, back on topic:

There was a place in Geneva that had an oyster/caviar bar and it was full all the time. Also, many people I knew in Geneva had caviar & salmon (not together) blinis and oysters for New Year. So I would say that yes some Swiss do eat caviar. Now will your neighbors? Had to say.

I'd start with a small plate and have a second option. And see how it goes. If the first plate goes off like wild fires then bring more. If not, bring out plan B.

We love caviar (hint, hint).

Are you sure they even like the blini?
;-)
I made some recently and while the taste of the buckwheat is "interesting", some are probably going to hate it, too.

But you can't make everybody happy all of the time anyway.

Correct - NO buckwheat. Authentic is ok....up to a point