Well it certainly isn't spamming, that word doesn't make any sense.
And the guys that are saying it's a dumb idea are clearly not on facebook. If a page "likes" another page, the likes don't go up. It just shows up on your page that you liked it.
When I use my page to like thing's, it's for company's that I buy equipment from so people see I use good equipment and I get updates from those companies.