What makes a dive bar? A ‘dive' is usually is a term that is applied pejoratively, or ironically, meaning some kitsch value is attached the bar. In reality they are a place to act out a bit - let out a bit of tension lubricated by a bit of cheap beer and heavy cocktails. No one's going to look down their nose at you for yelling or laughing too loud, or using an obscenity, or for the most part anything that isn't illegal as long as you would allow the same freedom to your neighbor.
Seattle is a beer city. Besides the well-known and large scale breweries such as Pyramid and Redhook, you can't swing an empty pint glass without it smashing against a local brewpub. Yet, if the lure of locally grown hops and grains isn't enough to satisfy your taste buds, you can try your non-glass shard wounded hand at the expanse of esoteric beer venues in Seattle.