From Michigan History, Volume 5, an article entitled Overland To Michigan In 1846:
"...they use up their good breath on the tariff reduction when they aren't settling the whole Mexican question [that culminated in the U.S.-Mexican War] .... ." "Some talk of joining the army for the bounty lands, but the job is too long for me."
From the Descendants Of Mexican War Veterans site:
Immediately upon discharge, Mexican War veterans were eligible for a federal bounty land warrant, redeemable for 160 acres of land anywhere in the United States. These warrants were also redeemable for $100 in scrip. Not a few veterans were swindled out of their warrants by unscrupulous land speculators who took unfair advantage of returning veterans ignorant of the warrant's true worth. Many parted with their warrant for $50 or less.
A TNGenes blog post has a transcription of a Mexican War bounty land transaction.