Well, they do, but unlike glasses, wigs are much more effective (though usually, wigs + contact lens works even better)
Lala is purely devilukean, and the pink hair should give you hint
Yes, Shinononos are part alien as well, but for some reason, Terran genes dominate Devilukean, so Tabane got the extremely recessive super strength + super intelligence + pink hair, while everyone else has normal features and enhanced body