6 night stay in Tokyo area only

My friend his wife and daughter are going to Japan and staying at the Royal Park Shiodome Hotel for 6 nights. They are flying Hawaiian Airlines from Honolulu direct to Haneda Airport. I told them if they are not planning to venture outside of the greater Tokyo area, they probably don't need a JR Rail Pass. Please correct me if I am wrong. I am assuming that while in Tokyo, they can buy the Suica or Passmo Pass and keep adding Yen to the card and use it for both JR Train, other train companies and all subways that connect throughout Tokyo. This would include the Yurikamome (train/monorail) to Odaiba. The cost for each 7 day rail pass is around $235/per person so that would be a lot of local traveling and they cannot use the JR Rail Pass when catching the subways. So, this is the situation and tell me if my advise to my friend and family is not correct.