That doesn't seem entirely fair of a comparison. If you built the canal, filled it with water, made sure it's wide enough for the boats that need to travel, etc, etc, then you are doing a useful service right. Apple has built something useful and yet we can all see it's wrong to take advantage of it to this extent, but we're having a hard time explaining why.

I think fundamentally corporations should only exist for the purpose of the public good. That is what's wrong with America and capitalism in many ways. It's not the shareholders but the public that they should answer to. If it does not serve the public good to take a 30% cut, then they should not be allowed to do so. As easy as that.