Further to Jamie's comments, many of us use certain coatings to avoid that "blocking" (sticking) issue on things like shelving, etc. A 100% acrylic that's formulated to be non-blocking or an oil-based enamel that cures hard are solutions. I don't do oil based so typically use SW ProClassic for this. But it's a tough finish to spray due to viscosity and you cannot thin water borne finishes beyond "just a little" and have to have the right equipment to handle it. Acrylics from Target, GF, etc., can be sprayed easier but are harder to find "locally" in most cases.
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The most expensive tool is the one you buy "cheaply" and often...