Now there is an interesting tack - fifth freedom between GRU and GIG.
It's how LAN manage to make GIG work, not sure which degree of freedom they have. But that's only in 320's and 767's, but I'm pretty sure that when I flew it in 2006 (GIG-GRU-SCL), noone got off the plane only new passengers joined. IIRC, there were (then) some European carriers serving the cities this way as well.