The honorable judge Learned Hand (yes, really) once said
> There is nothing sinister in so arranging one's affairs as to keep taxes as low as possible. Everybody does so, rich or poor; and all do right, for nobody owes any public duty to pay more than the law demands: taxes are enforced exactions, not voluntary contributions. To demand more in the name of morals is mere cant.
As long as companies are staying within the bounds of the law, it's perfectly reasonable for them to keep their tax bill as low as possible, and one might even argue that (for public companies) they're required to do so in order to perform their fiduciary duty to their shareholders. If you have a problem with the "loopholes" that companies use to lower their tax bill, you should take it up with the people who make the law, not the companies that follow the law.