Eating at home is fine, as I can easily work around the foods that don't agree with me and still eat heartily with the rest of my family. I don't force them to follow my diet.
I very rarely use a credit card, but I do if I know I have big bills coming and I need to stagger payment.
I do most of my shopping over the Internet because as a busy working mum I can do the supermarket shop when the kids have gone to bed.