Trim the garlic scapes, curl them up, and place them in a pint jar with a tight-fitting lid. We like to truly stack them on top of one another to make them pretty, and then fill in the center space with more tightly curled scapes, but you can also cut the scapes into bite-sized pieces and then just pile them in.
Work the chile, if you're using it, into the jar with the garlic scapes. Tuck it in the center, or work it in along the side of the jar so you can see it. (This is especially useful if you're making more than 1 pint and some have chile and some don't.)
In a small saucepan over medium heat, bring the vinegar, salt, and sugar with 1 cup of water to a simmer. Cook, swirling the pan if necessary until the salt and sugar are fully dissolved.
Pour the warm vinegar mixture over the garlic scapes in the jars to cover them (you may not use all of the vinegar mixture), but leaving about 1/2 inch of headspace at the top (between the top of the liquid and where the lid will be). Screw the lid on the jar. Let it sit until cool, then store it in the refrigerator for at least four weeks and up to six months to let the flavors blend and the garlic scapes to "pickle." The pickles will get more tender over time, but their flavor will stay garlicky strong.