He was in the wrong on several counts.
It doesn't make any difference if you were buying 6 inches or 6 yards, a measurement of fabric is exactly what it is.
I have NEVER seen a LQs that would even indicate they would not cut small segments from 20 bolts if that is what the customer wants. Obviously he has never worked at the shop during a shop hop.
Also, since you had several bolts with the same cut amount, he could have stacked three or four bolts at a time and made one cut for all three or four bolts. (I volunteer at our local shop during shop hop). We get bus loads at a time and have to work quickly to serve our customers. Since these gals are visiting so many shops, they always ask for small amounts from each bolt. What the customer wants, is what they get.
The price of the fabric , discount or not, should NEVER have left is mouth.
Owner's son or not, the owner needs to know and to refund your money or give you store credit for something you need.
Her son needs to attend salesmanship 101. You should not feel bad in any way, in fact, I would not have left the store until HE corrected the problem and refunded the money that he LITERALLY TOOK from you.
If you need a good lqs on line store name....my lqs is going online this month with hundreds of brand name high quality fabrics priced at $4.99 all of the time. I purchased Micahel Miller and Kaffe Fassett at another shop at $9.50 yd, and then dropped by her store only to find it at $4.99.
As soon as the store is set up for her online retail, I can let everyone know if you like.
Diana in Texas