It's not all about money. Things like actual time on the road, time getting back from games, time spent out of school etc. are also factors. Additionally, many rural schools don't have a choice. They are the only school in the county and must go elsewhere to play. Harder to sell long trips to administration when there are teams right next door. Another factor in the mid-sized schools is that while yes, they have gate and concessions, they have many other teams to support while your SW schools often have many fewer teams that are also traveling. Remember, it costs the same to haul a bus load of football players or 10 seats of volleyball players.
Finally, I'm not sure who you are saying is "crying". No one is saying "if only we could travel we'd be as good as (insert really good team here)." People are only saying that what they have been told by Ad's, principals, and school boards for years: "We play a district schedule to reduce travel."