Allowing a truly democratic amendment process could publicize much of the pork in many bills. It could result in a reduction in spending, thus a reduction in the amount of money committees control. Career politicians will not let this happen. Eighty-five percent of Rules Committee members have been in Congress for more than a decade. The Appropriations Committee decides how to spend nearly a third of the federal budget.
Career politicians aspire to chair one of the subcommittees that oversee a portion of the spending.
A subcommittee chairman may oversee spending for agriculture, education, housing, transportation, veterans, human services, or justice. Three quarters of the members on the Appropriations Committee have been in Congress for more than a decade. Every committee and subcommittee wants to spend more and more each year. Committees with shrinking spending also shrink in importance. That's not good for your career.