Question

Hello Rabbi.

In the Talmud (Berakhot 26a) a contradiction is brought between the Mishnah, which says that one may recite the morning prayer until midday (according to the Sages), and the baraita, where it says that if he did not recite the morning prayer he can recite the afternoon prayer twice—implying that the time for the morning prayer extends even after midday. And the Talmud resolves it: before midday we give him the reward for prayer in its proper time; after midday we give him the reward for prayer not in its proper time;
 
My question is: the Talmud’s answer here is rather strange… Since when does Jewish law deal with how much reward you will receive?? How do you understand this??