Except any war a major alliance fights that isn't against Florida/Fortuna/HOGG/Bowling allows one side to grow while the other isn't growing. It's considered a waste of effort. Everyone would need to buy into the idea that politics can involve people outside of those few alliances.
Hell, that mentality is what allowed Eclipse to grow into the powerhouse they have become - everyone was so focused on beating each other up, people so were worried about GGO, that eclipse was able to become a whale powerhouse with relatively little resistance.
Right now, Midgard is in a similar situation. They've grown almost continuously, have slowly but surely gained an upper tier, and really haven't had any major setbacks that I can think of recently, while everyone else has either taken a serious rolling or been in multiple wars. I've gotten way off track from the original post, but the idea remains - the biggest alliances are overly focused on themselves and setting each other back, as opposed to supporting and involving smaller alliances and spheres.