I'm not sure why this so quickly devolved into name calling.
As an integrator I'll add my own 2 cents. First let's define conduit. There are different types of conduit and as they say assumption is the mother of all evil so let's make sure we are talking about the same thing, or at the least add some qualifications to the use of the term. There is rigid conduit (of different flavors) and flexible conduit (also of different flavors such as metal and plastic).
Generally speaking flexible plastic conduit can be run fairly quickly and is of reasonable cost. It's an excellent method of "future proofing". Running conduit also does not mean that conduit has to be run "everywhere" (though it can be when budget/time/size of project allows). As an example, if a house has an attic and a crawl space or unfinished basement, it's an excellent practice to run a 2" or 3" pipe from the main equipment location to the attic, and also to the crawl space or basement. Now you have a method to get a cable to almost every area of the house in the future if you can drop down a wall from the attic, or shoot up a wall from the basement (assuming you don't have horizontal firewalls).
Even better (in addition
to the above practice) is to simply run a stub from the primary A/V location in each room to the basement or attic (if the room is on the second floor you run the stub to the attic, if it's on the first floor to the basement). In other words, let's assume you have a 3" pipe that runs from the basement to the attic and let's assume your equipment room is in the basement. And all the A/V locations on the second floor have a pipe that stubs up the wall to the attic. Now you can run cable from the basement equipment room by going up the 3" pipe to the attic, and then from drop right into any room on the second floor at any time via the short stubs you ran into the attic.
In a nutshell, I think it's hard to make a good argument against running some conduit
If you think you may want to run cable in the future I also advice you to spend a couple of hours in the house pre-insulation taking pictures of the interior of every wall and ceiling. This can be unbelievably useful later on down the line if you need to run a cable, and know what the inside of every wall looks like. It can be additionally useful if you ever need to service the house for the unfortunate things that can sometimes crop up behind the walls, and you have pictures of what is back there.