Facebook pages like LuxuryGifts4You are trying to lure unaware users by claiming that they have special prices which they want to give out for free.
The only thing the user needs to do, is to perform a specific assignment. The assignment can be anything. From liking a page to commenting something specific in the comment section.
There is no direct harm, but the chance is there that people will share personal information with these type of environments. Personal information which should not be shared with third-parties.