Oh, I forget to answer this question:
Excellent question and one that has been debated for many centuries. Some theologians have said the hogs owners were Hellenized Jews in violation of Torah Law, and therefore in rebellion against God. (And thereby very eligible for losing that which they should never have had.) Others have said that, as the name might be thought to indicate, The Decapolis was a Greek area inhabited by Gentiles but that they raised hogs in order to sell the pork to Hellenized Jews who were in that state of defiance of the law. Others have written that even though this was an area inhabited by Gentiles, that habitation was an invasion of a land promised the Jews and therefore by raising hogs it compounded the defilement of the land.
Some commentators have even claimed that sending Legion into the pigs was an act of mercy because otherwise the demons would soon have harassed/oppressed other people in that area—or even re-inhabited the demoniac man just as Jesus talked about in Matthew 12:45 and Luke 11:26:
Then the spirit finds seven other spirits more evil than itself, and they all enter the person and live there. And so that person is worse off than before. That will be the experience of this evil generation.
Therefore, some have suggested that the demons were unaware of the fact that Jesus would grant their request but thereby destroy them in such a way that they couldn’t harass anyone ever again.
Under that interpretation, to complain about someone losing their living versus people being spared terrible oppression for years and years to come, the complaint brings to mind some of Jesus’ conversations with the rabbis who hassled Jesus because he was doing good deeds on the sabbath and therefore doing wrong, even though his good deeds meant the end of terrible sufferings.
So perhaps it comes down to whether one cares most about drowning hogs or suffering people.
Finally, let’s take a look at this logic:
OK. Why would anybody say it takes very little water to drown a human? (Ya know, like pediatricians warn parents of young children, and as physicians warn people who are prone to seizures and thereby known to drown in bathtubs.) After all, people like water. Also, people like to use water-based lotions to keep their skin moist in order to keep it healthy. People will even visit beaches and build swimming pools. People clearly love water if it’s available to them! And they can swim.
Yes, by that logical examination of the relationship of humans to water, I have successfully demonstrated that humans would not drown and could not drown in some body of water—whether a permanent geographic feature or a seasonal one—even if afflicted by mania and seizures! And surely that logical analysis settles the matter.