There is no point in trying to justify the cost in counting the BOM, taking your watch for example, it uses a generic ETA caliber 2892-A2 (the "engine" in the watch) which is used in watches that cost 10% up to x10 of yours while it cost only $300-500.

I look at watches as a piece of jewelry more than an engineering item, they might or might nor keep their value but I like how they look, make me look and make me feel especially if there is a nice story behind the watch.