'If one is making theatre, the issues have to be immediately visible to the audience, so one needs a carrier.'-- Peter Brook
This technique has been around the theatre at least since Hamlet's Grave Digger carried on that philosophical discussion with our boy while shoveling up dirt and bones. There's nothing particularly interesting about shoveling dirt, or doing the dishes, or taking a bunch of photos, or cooking dinner, or getting dressed.
These kinds of routine physical activities do have a structure to them: at least they have a beginning and an end. And they can create a heightened sense of tension when woven through a scene with only mild conflict or even just discussion between your characters.
It's a very effective technique that can partially substitute for your Suspense Plot. It's even been used to great effect for the entire length of a play, though it's been a while since a contemporary playwright pulled this
Tony Kushner's second scene of ANGELS IN AMERICA: Roy is on the phone making and receiving calls -- the mechanics of this are funny, but have no real significance. This repetitive activity is woven through his side of these conversations -- which tell us a lot about Roy Cohn -- and Joe's attempt to figure out why Roy's asked him to talk. All of which takes about 4 pages.
http://www.vcu.edu/arts/playwriting/