This is a red herring. Dominos Pizza has no financial interest in effecting abortion policy, whatever the personal feelings of its CEO. Unless this unrelated political activism was disclosed explicitly to shareholders, the company could never legally lobby in this manner - it would be a breach of fiduciary duty to investors.
The reason for-profit companies lobby is to protect their operations and market. Anyone who beleieves a modern companies bottom line is divorcable from their operating political environment is delusional. No company can expect to compete without an effective say in politics. Given that, corporations have a duty to influence public policy (to their shareholders), and a right to let the public know how policy choices effect them (given that they are publicly held). This is why for-profit companies engage in political speech.
I don't think Ivan or others actually believe it when they say a profit-seeking company has no political interests. There's no way. You'd have to be completely blind to reality. This would be like saying you, as a profit-maximizing, individual have no interest in politics - an obvious falsehood, given the extent of government involvement in your individual finances and financial decisions.
This is altogether different from, say, Citizens United, whose purpose is expressly political. Here, too, the rights of individuals are protected only when the rights of Citizens United are also protected. If, say, George Soros can personally finance a political ad about the myriad benefits of a 100% income tax, why can't Al and I pool resources (through an articles of incorporation) to finance an ad arguing the opposite point? Is George's individual right to political speech greater or more protectable than our aggregate political rights? Granted, we are certainly more dangerous as a group than we are individually, but why is this a bad thing? The only rational purpose to this kind of regulation that I can see, is to limit the political power of individuals (by restricting their ability to organize).