I only like real coffee, from freshly ground beans and am pretty fussy about my pasta, dried not fresh, from a limited range of brands. I can often buy both of these whilst on offer and build up a stockpile.
I also like good parmesan cheese which I never seem to find on offer, so I buy it when I have Waitrose vouchers as I like theirs. DH has a dodgy heart so can no longer eat his favourite cheeses, we compromise by having a sprinkling of parmesan.
I'd rather pay a little more for good fresh tomatoes, and for better quality tinned chopped ones and passata. The taste is just so much better for a relatively small additional cost.
I used to only buy free range chickens, but I'm afraid that the price of these has defeated me recently.
Like other posters I have given up my regular trip to the hairdressers and have someone who comes to my home. She also leaves me with the products I need to do my roots before she comes again.
We do go out for meals fairly regularly which is our main extravagance. I think that I could easily give this up if we become really strapped for cash.