Chazal tell us that for 26 generations, from creation until Bnei Yisrael accepted the Torah, Hashem sustained the world solely because of his chessed. Only after Bnei Yisrael accepted the Torah did and could Hashem sustain the world based on what was deserved, using a merit based system. Does this mean that mattan Torah diminished Hashem's midah of chessed -- there was less chessed in the world as a result of mattan Torah?
Rav Hutner explains that to accept chessed without any sense of having earned it carries with it the taint of 'nahama d'kisufa,' the embarassment of taking a hand-out. Giving the poor man a job so he can earn his wages with dignity is the highest form of charity . Torah and mitzvos enable us to feel that we are earning our keep, even though whatever we do pales in comparison to the enormous amount that we receive in return.
Rashi writes that Moshe Rabeinu thought he could get away with reviewing the mishpatim two or three times for Bnei Yisrael until they knew the halachos, but Hashem insisted that, "Eileh hamishpatim asher tasim lifneihem," that the mishpatim be laid out like a table, that they be presented with all of their reasoning and depth. Moshe Rabeinu surely did not want to shortchange us from learning Torah. It's precisely because Moshe wanted so badly for us to know the mishpatim that he figured he would give us a 'kitzur shulchan aruch' version of the halachos. (There are some people who probably regret he didn't do just that.) Why should you have to struggle through Birchas Shmuels when you can just get the din straight away? But that's not what Hashem wanted. Demanding mental effort in learning s a far greater chessed than providing an answer key because halacha is mastered only through ameilus. (See Sefas Emes)