I agree that fat quarters is the more expensive way to go, and with losing some to fraying. I mainly use fat quarters when I'm appliquing, and don't have enough of the right kind of scraps. Its convenient to buy a fat quarter here and there for small applique projects.
~Bj~

At Rocking Chair Quilts, and any other local quilt shop, Fat Quarters are cut from the same bolts as any by-the-yard sale is. It is just not cut to order. It is a half a yard long and half the fabric's width. I don't understand the "FQs have a lower quality than bolt fabric" comment.
We have the bolts on the shelf and FQs that are cut from those bolts on a shelf immediate below; same fabric.

I've seen some FQs and jellyrolls that seemed to be not as tightly woven as others. Got them before I found a nearby LQS.

careful here. fat quarters are not always 18 x 22 because yardage is not always 44 wide. sometimes it's only 42 wide. sometimes you get shorted and sometimes what you get is a wide selvedge that's unusable. ask if you can see and measure before you buy that way. also, as said above, allow for shrinkage and fraying in the (pre)wash. also allow for waste pieces that may be too small for your project that wouldn't have existed if you had bought plain yardage.

I find FQ's a good addition to my scrap pile, especially if they have an interesting pattern or a colour I don't usually have on hand. I agree with Butterflywing, they don't always measure up the same. As for difference in quality, here they are cut from regular bolts.

You are very fortunate---in our local JoAnn's you very seldom find the same bolts as the FQs that are "wrapped" around a square piece of cardboard.
There are other FQs and you can see that these do come from bolts but these are rolled and you can see the difference.
Kutnso

Joann Fabric (forgive me as you have a LQS) has fat quarters that are purchased for the store already made up. Those are the fat quarters that aren't as good. I've shopped at several LQS and requested a fat quarter and they cut it from the bolt. Much better idea than the "factory cut".

I love FQ's, I do a lot of scrappy quilts and I don't have a lot of anything left over/// I make crumb quilts and they use every piece. 15 FQ's makes a great lap quilt.
None of my FQ's ever fray when I wash them for I do not cut anything off but surge every one before washing wit 3 threads of cheeeepes thread and loosen the bottom looper so it just pulls right out when dry.
Have fun, it is adicting you are warrned

yes 4 fq is one yard

Here is an image that may be helpful in understand FQs better.