The reasons for each set of fees are:

An entry fee is paid for the right to live in the facility for life. This helps cover the cost of the building and maintenance.
The basic-daily care fee and income-tested fees pay for the cost of care.
The extra-service fee is only payable if the facility has been approved for extra-service and the fee covers the cost of the services included in the agreed package accepted by the resident (such as newspapers or choice of meals).