My search continues, but thought I'd update for general information. Supermarkets in this area (Georgia) have been unresponsive to requests for 10% vinegar. They either can't get it, or they didn't look. And I'm sorry if I steered anybody to Sysco. They will sell nothing to you, which is understandable because they're a wholesaler, but they twist the knife by refusing to even tell you if they HAVE the product. I've never encountered this before but it's possible that their sales people are all legacy hires. You can tell I haven't quite gotten over my experience with them
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