Why do Legislatures think only of themselves?

Power... plain and simple. The longer a politician is in office the more likely he/she is to be more concerned with increasing his power base. It might interest you to know that statistically, ethics violations against Congresspeople tend to increase dramatically after they have been in office for 20+ years.

That's why we need term limits for Congress.

It's a combination of money from lobbyists and the Koch brothers. (Look up ALEC to see how many of your legislators are owned by them)

Because money is the root of all evil.

Its called lobbyist. They only care about what is handed to them in their pocketbooks.