Needs to be you and who’s army 
The initial farming rate is to be decided and then the network will adjust it. I suspect if there is reasonable uptake this could be 1 in 1,000,000 Get requests. So if you managed to do a million Get’s for your chunks (need over a million chunks to get past caching) then you may get a single safecoin if the farming request you might get is successful. This assumes the request works and you have good rank (stayed on a while holding chunks) so if you keep changing chunks then you need to multiply this a lot. Also this relies on nobody else doing gets on the data you hold (as it reduces your chance)
So if you create an app that gets used by a million people you may earn a safecoin per second with this guestimate or similar which is going to be much better for you and the network. This is why folk will think 1 in a million that’s nothing, but it all comes together when you look at the bigger picture really.