I certainly do think twice about carrying my 12.9 with me everywhere away from home/office but that comes down to whether or not i'm going to use it where i'm going as opposed to it being far too large to consider taking with me. I'm pretty sure I'd make the same evaluations had 11" been the max iPad size, and I'd likely make the same choices to take it with me or not. We're all different though, so I can certainly understand if for some people the size difference between the 11" and 12.9" is a concern.
As for home use vs a laptop it obviously depends on how one is using the device at home; having the ability to detach a physical keyboard, fold the keyboard back and out of the way, or just plain not ever having one can be important to some of us. I'm much more comfortable using an iPad to reference recipes or instructions while cooking or working on a project, or having media/news streaming on it while I'm doing just about anything anywhere in the house than I would be moving a laptop around to do the same things. It's not that the laptop wouldn't work in such cases, it's just that an iPad is a more space efficient and convenient device.