Jean, enjoy your new machine. If it brings you pleasure it is worth any amount of money. I went thru the same questions when I bought my Sweet 16; actually took some of the joy out of buying it. But I've learned to laugh off the comments. I've been working as a nurse for 40+ years so, yes, I can afford it--I'm very blessed. It helps me finish projects that have been sitting around for years. Ignore the comments and quilt away.
I'm going to get on my soapbox here: my BFF was diagnosed with Stage 3 ovarian cancer, did well for awhile but it has returned. She asked me a few questions right after she was diagnosed. Do you have a nightgown in a drawer that you're saving for something special? Do you have a beautiful tablecloth in a drawer that's too pretty to use? How often do you use your "Sunday dishes"? In other words, what are you saving it for? Use those items and enjoy them and the time we have here. I've made that my motto: use those Sunday dishes!