Let me play devil's advocate here (Oy).......
Lobbyists certainly do bring money to the table of politics, but they also bring information and representation. That information can come in the form of how a particular industry works, how it would be affected - both positively and negatively - by proposed legislation.
For instance - Suppose Congress were considering legislation that would import huge amounts of grain from South America during the winter time, assuming that in the winter we can't grow grain, while South America can. Seems to make sense on the surface.
But along comes the USA grain lobby that says "Hey wait a minute Mr. Congressman - we DO grown grain in the winter - it's called 'winter wheat.' Now Congress has been apprised of a fact it might not have known and it can take this fact and incorporate it into the legislative decisions.
Another instance.......suppose you belonged to a group such as the League of Women Voters or the ACLU, or SPCA, or MADD, or NAACP, - well pick your group. You might hire a lobbyist to represent your group's interests in the halls of government. The members of the group can't all go to Washington (or a state capital) and stay there for days and days while legislation is being written.
Most of us, at some time, have been represented by a lobbyist for a variety of issues - like unions, or women's issues, or lobbying for more research on a disease (like breast cancer, heart disease, etc.).
Like anything else (well, almost anything else

) lobbyists are not ipso facto a bad thing.