Likewise, I could say that anyone who doesn't want to watch them all at once doesn't have to. You can choose to watch only 1 episode a week.
For me, and for a significant number of attentive television fans, a big part of the experience is reading the nightly discussion post by our favorite reviewer and discussing the episode with everyone in the comments section. I'm part of the very active AVClub community and teasing out what happened with the everyone else who just watched the episode greatly enhances the viewing experience.
For FX's The Bridge whose lead character falls within the autism spectrum, a certain commenter who is also on the autism spectrum writes a few hundred words that illuminates what it's like going through life in a very different way from most others. I have learned a great deal in the process, and it's something that is possible only because one episode is available per week. If they were dumped at once, maybe I'd rush through the whole thing at once, or she would and this exchange would never have happened.
I would definitely not mind 6 episodes per season of high quality entertainmen (aka British TV production schedule).
I wouldn't know about the water-cooler effect because I've never actually experienced discussing with other people last night's TV.
But getting it all at once is like peeking at your Christmas presents early: you think you want it, but it spoils some of the fun, the eventy-ness of it, and the social context created by a shared timeline (the so-called "water-cooler effect").
Anyone who doesn't want that experience can still wait until the whole thing is out, probably just a few months, at which point it will still be available in the binge library, presumably forever. (I know some who prefer not to start a new series at all until the entire thing is finished, which is also okay.)