A lot of times, when company are marketing new products or discount, they will hide the offer from their website since they only want people who had viewed their advertisement to enjoy the discount offer. Therefore, most offers will only be available when you click through some designated link or make yourself a member of their group.
In RunHotel, they will gather up all discount information and let us users to gain the most out of it with the least effort. For more information, please refer to their website.
RunHotel Website: http://www.runhotel.hk/