In Arms and the man act 3 why does Raina say that Bluntschli is incapable of noble sentiment ?

Bluntschli, a Swiss mercenary who clambers through Raina's bedroom widow as he flees Bulgarian troops, best represents the qualities promoted by the play: realism and pragmatism. Bluntschli is unconcerned with romantic ideas about heroism or conduct in war; he is concerned with professional conduct, efficiency and survival. This is essentially why Raina accuses Bluntschli of being "incapable of gratitude" and "incapable of any noble sentiments." Ironically Bluntschi sees through Raina's sanctimonious attitude. Raina appreciates this more than being adulated and worshiped by Sergius.