Pink, red and purple colour patterns are not uncommon in grasshoppers and katydids. Colouration is determined by a combination of genetic and environmental factors. Nymphs developing in moist green vegetation often have a preponderence of green morhs whereas those developing in a dry brown background have a preponderance of brown and straw coloured morphs. Black forms are common inburnt habitats. These colours presumably aid camouflage and protection from predators. I'm not sure what the pink colouration is due to. I have sent separately an example of an adult with purple markings
Interesting, but the purple blends into the background a bit, especially the way it is broken up. I can't think of anywhere in the area where pink would be useful camouflage, at least to human colour vision. Perhaps the colour would be less visible to the grasshopper's natural predators?