A chemist and a physicist on a couple of threads here changed my mind about what I thought I knew about patches.
Evidently some patch kits have chemicals in both the patch and the fluid, catalyzing the vulcanizing of the rubber. IF it actually does vulcanize it. Therefore, I personally decided just to simplify it and abandoned the idea of getting bulk patches and/or fluid. A reputable patch kit would presumably at least have the right chemicals to work together. Objectively I don't patch tubes all that often, the patches tend to work more or less permanently, and don't cost all that much. So you reach the point of just buying what works, even if it costs 2 or 3 times as much as bulk it's still just a dollar or two.