H.G. Wells is a writer of his time. His thinking is scientifically unsound from a modern standpoint but it represents very well the fears and hopefulness of his generation. As such, the writing style itself may appear bland, slow-moving, or pretentious. This is not a failing in the book but in the reader.
Despite the obvious scientific commentary by Wells in this book, the larger meaning focuses on the means by which vast social changes occur. A particularly illuminating section of the work details the impressions of a man emerging from jail. He had been removed from society since before the arrival of the Food and upon his release, the seemingly gradual changes in the function of society are seen by the formerly imprisoned man as incomprehensible. When he asks his brother to explain the incredible changes, his brother responds as though all the changes are merely life-as-usual.
Since the sections are written from differing perspectives, it is difficult to determine whether any narrator or the author side with the Giants or the regular men. Wells' writing might favor the Giants. When the Giant children grow up and begin to determine their own fates, they are written as far more sympathetic characters than their normal-size counterparts. Furthermore, the Giants' speech and beliefs are more noble and hopeful and future-minded than the normal-size people. However, after the first battle, the speeches of the Giants at the very end of the book may serve to persuade the reader that they are to side with the regular-size people. The Giants are concerned only with largeness, with dumping quantities of the Food on cities so that children (against the will of their parents) will begin to grow. The Giants' plan is to continue this attack until eventually the tide turns in their favor and children attacked by the Food begin to outnumber the older generations of regular-sized people.
But it is clear that this an attack--an act of aggression which should be chilling. The Food does not work on adults - only on children. One can imagine mothers and fathers horrified that their beloved children are slowly becoming the very monstrous creations they fear most. Furthermore the Food is essential. Once a child has been exposed to the Food, it must continue to get the Food until it has passed through puberty or it will DIE. These parents whose children have been exposed now face a horrible choice: procure more of the Food and keep feeding it to the child or allow the child to die.
But none of that appears in the book. It is simply the logical conclusion to the ending speeches of the Giants who intend to continue to expose whole cities to the Food. But as mentioned, the Giants are obsessed with bigness. At the end they take no more thought for themselves and their struggles against a hostile world. Their one goal becomes bigness and more bigness until the world will be too small to hold them. Unlike the creators of the Food, the Giants never even imagine that just because they CAN, is it true that they SHOULD?