The biggest problem with the rain isn't getting wet; its the lack of sunlight, slippery driving conditions and constant threat of rain.
Even the described 20% chance of rain in any given hour is surprisingly inconvenient. Riding a bike to work/school or jogging are things that I think are best if turned into habits -- done at specific times on specific days -- not on the spur of the moment after looking at a weather report. And executing a picnic or hike with any decently sized group of friends is barely possible on a moments notice.
Seattlites need to call a spade a spade. If you like doing things outside (and judging by how full the city parks get on any remotely sunny day I think a lot of Seattlites do), the weather there is consistently inconvenient for about 10 months out of the year.