When and why RMAN catalogs the files in recovery area during a Restore/Recovery operation?

Hello Experts,

I have come across strange thing as far as RMAN Restore/Recovery is concerned. I have a Media Manager which generates the RMAN script. With this I am trying to restore and recover a database to a PIT of a backup control file.

MML output-

 RUN { ALLOCATE CHANNEL ch0  TYPE 'SBT_TAPE';
SEND 'BSA_SERVICE_HOST=192.168.1.34,NBBSA_TOTAL_STREAMS=1,NBBSA_JOB_COOKIE={6F91F387-FFCD-4DD2-915A-0B2E657A6F86},NBBSA_DB_DEVICE_NAME=Oracle-Linux::\\RHEL5-64-11gR2.oracle.sym\orcl'; 
RESTORE CONTROLFILE FROM 'BE_05ou2gq1_1_1'; 
ALTER DATABASE MOUNT; 
RESTORE DATABASE; 
RECOVER DATABASE;