Unfortunately, most things in life come at a cost, and in the case of the Gladers, sometimes that cost is a human life. Throughout the story there are examples of people giving their lives (or at least risking them) in order to benefit the greater good. Sometimes there are selfish motivations, and sometimes there aren't, but it's always pretty rough when an innocent person has to die. The bottom line is that in all of the scenarios that involve sacrifice, an element of choice is also involved. The sacrifices we witness range from meh-level (come on, we all knew Gally had to bite the big one) to sobbing-hysterically-while-pounding-our-pillows-level when Chuck throws himself in front of the dagger meant for Thomas.
Questions About Sacrifice
Whose sacrifice did the most good? Thomas's, when he went into the Maze to save Alby and Minho? Gally's, when he volunteered to be the guy the Grievers get on the first night? Chuck's, for saving Thomas at the end? Alby's, for distracting the Grievers long enough for Thomas, Teresa, and Chuck to get to the Griever Hole?
Was Chuck's sacrifice necessary to the story? Or was it just a sadistic plot twist from the author?
Why do you think the author chose this particular plot device when getting his characters out of their tight spots?
According to the memo in the Epilogue, WICKED scientists orchestrated the final variable of Chuck's sacrifice for Thomas. But how did they know he would jump in front of the knife?
Chew on This
If Chuck hadn't taken the dagger meant for Thomas, our group of merry men (and one woman) would be leaderless, and the Creators were totally okay with that prospect.
Gally's sacrifice is more of a convenient pseudo-suicide, seeing as he never wanted to escape the Glade anyways.