For stand builds I am lucky enough to have a jointer and a planer. It makes life so much easier to bring the stock down to a common identical size before assembling. It really highlights the differences in board dimensions when you have a stack of 2 x 4 lumber and some of them go through the first pass of the planer taking a pretty knarly bite off then others aren't even tall enough to hit the planer blades.
A couple months ago I was at Lowes and they just brought out a fresh stack of kiln dried 2 x 4's. We needed a dozen for a project at my girlfriends place (Actually my gf's place IS the project!). I ended up with 40 really good solid straight sticks after going through half the stack. My gf couldn't understand why we needed 40 2x4's. I tried to explain to her that you have to grab the good lumber when you can because in a week there will only be the picked through left overs remaining.
If I can get straight, solid and not twisted I am happy. I will deal with size variations. For framing it doesn't matter, for stands, shelving etc. I am lucky enough to have the proper wood working tools. I just chuckled when the video said "The EXACT size of a 2x4!"
You are right though... my local lumber yard has much better lumber. The plywood they carry is a whole lot better than borg plywood... the lumber store plywood is even FLAT!!!!! Not with a nasty bow in the sheet like the borg plywood always has. Darned if I can figure out why the borg employees can't figure out how to lay the plywood on a flat surface!
Unfortunately the lumber yard caters to contractors who shop during the work week and they are not open on weekends when I shop.