There are several problems with this point of view. First, those who are greedy may throw their support to a harmful ideology (such as happened with German business and the Nazis prior to the Second World War). They can cause great harm in their own right, such as the Congo Free State or the British East India company.
Third, they can hold ideologies and attempt to pursue their greed in a way steered by their ideological blinders. For example, the Russian sell off of oil assets was expected to be a massive generator of economic value by a lot of generic business people, and it was - for a clique of well-connected oligarches. Everyone else who wasn't so well connected didn't do as well as they thought they would.
And so I don't get worried about corporations influencing governments. As long as they're kept at one anothers' throats (capitalism) things are working more or less the way they should.
This is the third great division of power in US politics.