"Going without", even if it is voluntary, can help one to 1) appreciate the blessings of everyday life that we take for granted throughout most of the year and 2) develop compassion and empathy for those who have less and are deprived through poverty and lack. Ideally, when we have purified ourselves through these periodic fasts we emerge more grateful and compassionate. I think that has something to do with the underlying philosophy of Ramadan and Lent.