I do event planning for a large annual convention. At the Marriott involved we have a master account which picks up the charges for all rooms for our volunteer staff. The only way that our volunteers (including myself) have been able to get credit for nights and get the MR points is to pay for our room and get reimbursed (and supplying our MR# of course.) The rate is the same whether it is paid through the master account or paid individually as it is all part of a negotiated block of rooms.