The problem is the wiki article alludes that this line emission from atoms breaking off from the material and having chemical reactions in the flames around it is not entirely responsible for enhancing its glow.

edit: idk why i considered gases (which i thought i know) and solids (which i know i don't know) as so different. Kirchoffs law applies to solids too, so if a solid is a poor absorber at a wavelength, it must be a good emitter.