The Big profitable games are by teams that are both good and probably in the same conference, that does not make it a rivalry though. Some grow into that like the ones you mentioned. There is an element to time that make some rivalries big games for their teams fans even when both suck. That was somewhat the case during the drought, fans still got up and were more interested (and spent more money) when the Bills played the fish. My overall point is rivalry does drive revenue but the biggest games are not necesarily the best rivalries.