Im still confused as to exactly when or where this book takes place in. I know it's irrelevant to the plot but it just keeps ticking in my head, I couldn't help but recall my time in officer's school where I could have come out a lieutnant with a cushy salary and "brothers" from the same caste, specially since my country hasn't taken major action in a war since a couple of relativly minor WW2 skirmishes in Italy. I remember carrying some regret in me for living, the academy was out in the middle of buttfuck nowhere with only hillbillies who all seemed a bit mentally ill and unfullfilling sex so I could not see myself staying there. A pinch of regret washed over me because I could be having cushy state benefits, but that book made me realise that lifestyle was not for me
As for the horse I think it's more to show the absolutely unfair nature of military life and regimental rules. By all means any sensible person would have called that off but some people, specially in that type of career, are absolutely stubborn about regulations. Im pretty sure that this is why Simeoni got the upper hand over Drogo into becoming chief there, because as soon as he got the warning for trying to use the spy glass thingie he immediatly started bootlicking his superiors and pretending nothing ever happened. Also as >>24635013 and >>24635876 have pointed out it's probably another bait into leaving Drogo there, constantly on the edge of glory.