In "The Crucible", why is the issue of Parris's salary raised?

The issue of Parris’ salary is raised in Act I when he is having a conversation with John Proctor and Giles Corey in which Proctor and Corey are expressing his distaste for Parris.  Parris makes a comment to Giles in which he says,

“Mr. Cory, you will look far for a man of my kind at sixty pound a year!"

The three men continue to argue about how much money Parris gets versus how much he should get.  Parris thinks that he should get that salary, plus own the house that the village provided him with, and get free fire wood to warm his house.  Both Proctor and Corey disagree with this and think that his salary of 60 pounds a year is more than enough.  Additionally, Proctor makes a point of telling Parris that they never had a reverend who demanded as much as Parris has demanded from Salem village.