I would think that the last thing to skimp on is the stabilizer. I've only made a few t-shirt quilts for my own kids and the stabilizer was essential for the knit fabric. Sometimes the knit fabric was cheap and the stabilizer kept the quilt together. I would be really upset if I paid whatever price for a quilt and it became distorted after just a few months and even worse after a wash. I cannot replace the ruined meaningful t-shirts! I'd be really steamed at you my trusted quilt maker.