John Fund details a major exception to the Congressional gift ban:
Take something as simple as bans of gifts from lobbyists. In their favor-seeking, all of the lobbyists visiting Capitol Hill are bound by House and Senate ethics rules that cap most individual gifts at $50 per elected official or staffer, with an annual limit of $100 per recipient from any single source. But local governments, public universities and Indian tribes are exempt from the limit, so they are able to shower members and their staffs with such goodies as luxury skybox tickets to basketball games and front-row concert tickets.
Having members or their key aides attend such free events in the company of glad-handing university presidents and local government officials winds up costing taxpayers a pretty penny. Much of the explosive growth in earmarks has been directed to local governments and universities. While they are entertaining members of Congress, you can bet the hosts at such events are making the case for pork-barrel projects that range from a new building on campus to a new bridge. Some of the projects are ludicrous--the infamous "bridge to nowhere" in Alaska comes to mind--but most others have some benefit but simply can't be justified as a federal priority.
There's no doubt that spending to lobby for these projects has exploded. Universities and colleges spent at least $75 million in 2005 on lobbying according to a study by USA Today. The Chronicle of Higher Education reports that $2 billion in grants flowed into higher education in 2003. "The return on investment is simply too good to pass up, which is why so many lobbyists now can convince local governments they will recoup their steep lobbying fees by getting far more in earmark dollars back," says Ronald Utt, a former federal budget official now at the Heritage Foundation. The number of lobbyists specializing in earmarks has doubled in the last six years.
Read the whole thing. It's just another demonstration of how difficult it is to change how Washington works.