The US Chamber of Commerce, as we have discussed here many times is not a pro-market organization. It is pro-business. These are 2 fundamentally different things.
Being pro-market means being for competition, innovation, and entrepreneurship. Being pro-business is about limiting competition, making sure innovation is managed (at best, and for the established firm) and keeping upstart businesses with new ideas and better business models under control (usually through laws).
Congressman Justin Amash just beat his primary opponentin a race that would not have happened had it not been for campaign money poured into the anti-Amash camp by the US Chamber of Commerce, the Grand Rapids Chamber, and the Michigan Chamber. Amash, who, as a politician has committed his fair share of political crimes, at least has had the decency to oppose a variety of cronyist measures and refused to fund several bailouts and bills designed as special favors for business interests. So, naturally, while claiming to be “pro-free-market,” the US Chamber of Commerce has gone after him for not spending enough government money. This is not surprising. Business groups like Chambers of Commerce are not free-market organizations at all, but are just rent-seeking lobbying groups looking for government favors.