Whilst on vacation I ordered a gin & tonic. It was off. I couldn't say exactly what was amiss about it, but it was Not Right. When I asked the bartender what gin had been used, I was informed it was Fleischmann's. The next G&T had Hendrick's, and it was much, much better. Interestingly, the night before I had also had a gin & tonic, at a different establishment, and I saw that the gin used was Barton's - a brand I'd not encountered before. The result was acceptable.
Later, I checked out a couple stores and saw that while Hendrick's was, as expected, top shelf gin, both Fleischmann's and Barton's were bottom shelf. And I mean that quite literally - they were on the very bottom shelf. There was a slight cost difference, and that difference mattered. The buck or two more for Barton's was clearly worth it. Barton's is inexpensive. Fleischmann's is cheap. And I can taste the difference, even with the quinine of tonic present.