Wow, I don't know where to begin. Patek pioneered the wrist-watch (1868), and received patents for the keyless watch (1845), perpetual calendar (1889), double chronograph (1902), gyromax balance (1952), first quartz watch (1959)... the list goes on. Look Rolex has its own share of horological achievements, most notably for the first truly waterproof and dust proof watch, but both Patek and Rolex are unjustifiably overpriced, and much of this is driven by marketing.
It's fine if you think a Patek is overpriced, but most watch experts would consider the Patek Calatrava to be the quintessential dress watch. By their very nature, dress watches are supposed to be understated and elegant. The price is in the quality of the finish of the case, and the movement.
Maybe in your social circle, the Rolex is the undisputed crown of achievement, but there are many who would consider a Rolex to be declasse, and this is why Carla Bruni gave Nicolas Sarkozy a Patek Philippe to replace his gold Rolex Presidential when they got married.
Look, it's clear from each of our respective avatars where our tastes lie. I'm willing to concede that a Patek is overpriced but I don't think it is any more overpriced than a Rolex. I think you're primarily responding to the genre of dress watches in general, and I assume they don't appeal to you. But not every $20K watch has to be a 18K gold watch and bracelet, or something studded with diamonds, to justify its cost. The reality is that all luxury watches are overpriced in their own way, and indeed, this is part of their appeal.