Like QuiltingVagabond, I am a sucker for a good deal. I also tend to buy in 2 yard or more increments. If I think it will make a good border print I buy 3 1/2 to 4 so I can cut LOF. I also save scraps at ridiculously small increments. I like offset log cabins made with 1 1/2" and 1" strips so will save a piece as small as 1" x 1 1/2". I have baggies with premade HST as small as 1 1/2" square with plans for them in a scrappy quilt. (they are my leaders and enders ala Bonnie Hunter method). I also have baggies with other sizes. 2" strips are set aside in varying lengths for a one day strip quilt or possibly some other project. I refuse to buy precuts. But I have won fat quarter assortments and the one time I ordered from Missouri Star I got a charm square package for free. These are always problematic for me because I usually love the assortment but they are not what I would usually purchase for myself (in terms of colors and prints) so I have nothing in my stash to go with them so I end up buying yardage to go with them and end up with..... more scraps! But they do get me to step outside my color/print comfort zone which is always good.
I try not to binge shop too often. And right now I have enough yardage that I don't feel compelled to go on a FART (Fabric Acquisition Retail Therapy) trip any time in the near future and I have plans for a lot of what I have. My fabric tastes haven't changed too drastically, thank goodness. So I still love almost every piece in my stash and want to use it. There are a few yards of that "sale too good to pass up" that I do like the fabric but am not totally in love with it. Right now my stash is sorely lacking in solids. I need to beef that area up a bit. I can always use neutrals and background blenders in all the varying shades of white, cream, ecru, eggshell, etc, they just aren't as exciting to buy.
But a necessary addition to anyone's stash.