The gold ones were definitely for sale both online, in the shops, and in department stores (one of the big London department stores has an Apple Watch counter).

Personally, I think it was more of a marketing gimmick: send a few out to celebrities for some buzz in the fashion press, and get the tech press to write about how Apple are "going after the Rolex end of the watch market"... even if they don't sell many, it was good PR for the first series of watches.

And for consumers, they could try the gold one on in the shop, sigh that they don't have $10,000 and then buy the $300-$500 one.

And it wasn't really the headphones they were after - it was the people and music.