jurisdiction

The Appropriations committee is widely recognized by political scientists as one of the "power committees," since it holds the power of the purse. Openings on the Appropriations committee are often hotly demanded, and are doled out as rewards. It is one of the exclusive committees of the House, meaning its members typically sit on no other committee. Under House Rules, an exception to this is that five Members of the Appropriations Committee must serve on the House Budget Committee—three for the Majority and two for the Minority. Much of the power of the committee comes from the inherent utility of controlling spending. Its subcommittee chairmen are often called "Cardinals" because of the power they wield over the budget.
Since Congress is elected from single-member districts, how well the member secures rewards for his or her district is one of the best indicators as to whether or not he or she will be reelected. One way to achieve popularity in one's district is to bring it federal spending, thus creating jobs and raising economic performance. This type of spending is often derided by critics as pork barrel spending, while those who engage in it generally defend it as necessary and appropriate expenditure of government funds. The members of the Appropriations committee can do this better than most, and as such the appointment is regarded as a plus. This help can also be directed towards other members, increasing the stature of committee members in the House and helping them gain support for leadership positions or other honors.
The committee tends to be less partisan than other committees or the House overall. While the minority party will offer amendments during committee consideration, appropriations bills often get significant bipartisan support, both in committee and on the House floor. This atmosphere can be attributed to the fact that all committee members have a compelling interest in ensuring legislation will contain money for their own districts. Conversely, because members of this committee can easily steer money to their home districts, it is considered very difficult to unseat a member of this committee at an election—especially if he or she is a "Cardinal."
In addition, the ability to appropriate money is useful to lobbyists and interest groups; as such, being on Appropriations makes it easier to collect campaign contributions.