All three of these verses are clearly written long after the events. They corroborate Zeniff’s declaration that he was overzealous to obtain the lands, and these verses begin to explain the reason. They are certainly written about an enemy, and are not intended to be objective. Zeniff could only assume that the reason that king Laman allowed Zeniff’s people into the land was to subjugate them. While possible, it required great effort in relocating people who had already been there, and then waiting a long time for the benefit. On the other hand, king Laman must have seen a benefit, else he would not have gone through the effort. Still, it took twelve years for the Lamanite plan to begin to be effective.
Verse 12 suggests that the Lamanites were lazy and idolatrous. That they were idolatrous was quite probable. That they were lazy could not have been true. An agricultural people could not survive on laziness. What Zeniff means is that they desired to receive tribute payments from dependent cities. For the Lamanite king, it is very possible that this was the intent, and it was likely mirrored in the purely Lamanite settlements that were also beholden to the Lamanite king. Perhaps taxation was what it was called when one’s own people paid to support the government. When other cities paid to support the overking, it was tribute, or in the word that Zeniff’s people will use, bondage.
The statement that “they might glut themselves with the labors of our hands; yea, that they might feast themselves upon the flocks of our fields” is a rather accurate description of the effect of tribute payments from a dependent city to the ruling city.