Hi Mogget
The package is large because it contains a selection of different installers and also covers FS2004 and FSX installations.
The Landclass and Coast entries are, in your case, dummy entries, put there to assist the overall installation process. A customer with FSX and photoscenery will have the appropriate package automatically installed for them and you will find if you look in the folders created within the RAFCollection install, for Landclass and Coastline, you will see that there are actually no scenery files there.
I, personally, had no hand in setting up the installer and what I have said is my understanding of what it is trying to achieve.
I hope you will find that the appropriate scenery is present on your system.
Iain
Scotflight