This is probably because we have not added cemetery categories "pre-need," and have waited until someone adds the category to a profile, which has been the categorization philosophy with regard to almost all of the hierarchies (outside of place categories, many of which were set up in advance of use.)
Many of the WT cemetery categories have a handful or fewer profiles attached.
I used to participate in FAG quite a lot, but have trailed off in the last couple of years. I like having the ability to add sources and write a story of a life, linking entire families.
I make corrections to my FAG memorials often, but have had only spotty success when I suggest corrections on FAG, even when I send sources along to the memorial manager. This is one reason I've all but abandoned the site. There is not much merging of memorials going on any longer either. I used to be able to email info@findagrave and they'd merge memorials and cemeteries. Now it seems to be up to the memorial managers to work it out. That's not fun at all.