Normally I/we wouldn't do this, but it was a bit of a hurry-up thing.
One of the guys I work with has this friend, who is an artist (painter). She sells her work in craft shows and the like. Over the last couple of years, she has started displaying them with frames too. It's a very simple poplar "L" shaped frame that has one leg under the frame and the other wraps around, leaving a 3/8" gap between the frame and the canvas. It is intended to "be there" but not take away from the artwork.
That's were I/we get involved, making the frames, and where the problem came in this time.
She placed her request a couple of weeks ago, but we had plenty of time and other priorities, so the wood was never ordered. Then a few more details of the timeline popped up and this became a hurry-up job.
It was decided yesterday morning that we really needed to start that day, which means that the normal suppliers were out. Box store to the rescue? Hopefully? They are generally not known for the quality of their wood. In this case, quality being as much about color as anything. I was pleasantly surprised. Not only did it look pretty good, they had 10 and 12 foot lengths too.
This is where the funny part comes in. The price sticker on the shelf was in linear feet? While this is not that odd to pros, I can see this being weird for homeowners. At most of our suppliers hardwood is priced by the boardfoot, with the exception of trim pieces that are by the linear foot. The big confusion at the box store came for me at the rack itself. They allow you to actually cut the boards right there in the aisle? They have this sort of miterbox type thing, with a hand saw. Apparently, you are not required to purchase the whole stick? That just blew my mind. It is so wasteful. There were several off-cut pieces sitting there in the racks that may never sell. Who wants a 1" x 10" that is only 12" long? Somebody cut that off of a longer stick and left it behind. A 1" x 10" x 10' is certainly more valuable than 10 individual pieces of 12" each.
If it was scrap in the shop, I would keep it, but I certainly wouldn't pay $6 or $8 for it. I don't remember what the price was at that width, we were getting 1" x 4" for $2.44/ft, which is considerably more than the regular source.
Allowing customers to cut this has to be costing them money in waste? Which has to increase the price in general doesn't it? Seems silly to me. At the other places, you can get as close to your goal length as you can by doing the math on the lengths they have, but you are buying whole sticks.

I haven't done the math but my assumption is permitting DIY'ers to buy only the 87" they need is worth the waste considering the price. Another hunch is many people only need 3-4-5' or so an, if forced to buy 8-10', they'd loose sales.

There is also the ability to haul longer stock. Folks may be whacking a full length in half for transport reasons.

I downgraded from a truck to SUV a couple of vehicle-cycles ago at the insistence of the boss, only regret it when it comes time to buy material. I can run 8' length inside by padding the drivers center console but it's a PITA. Next time I'm back in a pickup...

RMW

No argument, now that you've pointed it out. They've had the cutting station around it so long it just kinda blended in. Most of their trim is sold similarly.

RMW 

Here the orange store charges by the foot but then checks length and the register rings up by the inch.  Cuts down on shrinkage but is a pain when someone in front of you at the register comes up with a precut cart of 15 items for a project to eliminate as much waste on their end.

Peter

Just a note, but you can also return by the foot purchases by the foot. I watched a contractor return about 30 various lengths of trim. He’d purchased them all as 12’ pieces, used what he needed, and then return all the scrap.

I’m sure by the foot comes with costs but when you peddle in garbage lumber like they do you throw away a significant portion as is (think about all those twisted 2x4s or split 2x12s). A twisted by the foot 1x4x120 stick of poplar can get cut at the twist and sold as new.

-r

Home Depot sells “Project cuts” (or something like that).  They are 2’ lengths of stock.  I wonder if they chop up their accumulated scrap.  It is about 1/2 price.  Most of the cabinet doors I build can be made with 2’ lengths. So I watch for that.

The thing is though, all of these "feet" are not equal. Ten pieces that are 1 foot long and a single stick of 10 feet are not the same thing. Sure, they are the same amount of wood, but that still not the same thing.

If their 1-foot sections are usually twisted/warped, are they REALLY not the same thing? 

I definitely agree with what you're saying.  When you're talking slabs, a board-foot isn't a board-foot if you need a live edge, a book match, or really anything stable over about 1x4, it seems.