In my opinion these guys are very greedy. The hotel is very basic and low quality considering "Mercure" name. Their internet web site is deceptive. Implied that breakfast included but was told not on site. They make you pay for everything as much as they can.
I did stay for three nights with my family in Mercure Grand Umm Al Qura , really nice rooms equipped with good confort , i didn't have problems to reach The Haram , only about 800 meter ( about 10 minutes walk to Kaaba) with reasonable prices..I recomend it to my freinds, not crowded as Hotels facing haram..