It is true, 90% of people who enter RnR races (or any other big city Marathons for that matter) don't care who wins neither do they know their names.
During the NYCM, about a million people are along the road but most are their to support their loved ones, not for the elites. I have been watching the NYC Marathon and Half Marathon for many years now. It is always the same: anonymous clapping, then "GO KARA", "GO RYAN" then anonymous clapping again followed by ecstatic cheering when their loved ones come.
So from a business perspective, it makes sense for NYRR (or competitor) or whomever to pay high appearance fees for popular runners (Hall, Kara, Shalane, Meb, Rupp, Ritz), but athletes like Mutai, Makau, Kipsang etc. bring nothing to the table for those 95%.
NYRR already pays a lot more money for Hall or Meb than for your average 2:09 Kenyan. How's that fair?