Well, the NBA also has salary caps. In BB, if the best teams get rewarded with extra income from more games, it's like the rich getter richer and that can translate into buying better players with higher salaries and making it even harder for other teams to catch up to them. If the Lakers make a ton of money by making the playoffs and winning the NBA Finals, the team owners pocket the profits and have an easier time maxing the salary cap (or going over it with contract renewals, etc., within the rules of the NBA). So it's not fair to compare the NBA to BB in this respect.
But it's because we can't compare this issue to the NBA that I also say that BB just has a different system, one that includes promotion and relegation, much more like soccer (football to the non-Americans). That's why I'm not so sure that the system has to do much for the 5th place teams, especially since we all live by the same rules. If a team REALLY hates 5th place, they can try to lose games to get into a relegation series and hope they don't get upset and end up demoting.
Don't ask what sort of Chunks they are, you probably don't want to know. Blowing Chunks since Season 4!