Having come into quilting late in my sewing hobby, I found for garments & home dec, a machine that could sew a good buttonhole could usually do the rest of what I needed well, too. Buttonholes require precise, dense, uniform stitching and only a good machine can do them well. Ironically, my old Singer Genie tends to do a better buttonhole than many of the push-button buttonhole machines that are out now. That said, the convenience of something that sews & cuts your buttonhole with a single touch of a button is pretty awesome when it's done well.
For home dec, I would use large buttonholes for shower curtains, pillows & sometimes even with drapes (tab top drapes). It's a very important & useful feature... except for quilting where we don't really like putting holes in our work.