Or maybe "like" is an term with no formal meaning here and I'm just "liking" page because that's what we call "bookmarks" on this particular website. Or "favorites", or "starred", or whatever. I might even be "liking" the page because I want to remember what a bunch of douchebags the associated outfit have been to me or my family in the past and want to keep an eye on their marketing babble so that I can warn friends/family not to be caught out by it.
When I "favorite" a website in Internet Explorer, nobody thinks it implies I commercially endorse whatever organization's page it was. Why should a "like" infer that.
Of course in practice I firewall Facebook at the router.