I'm going to have to agree with Cid that a 5th-seed team in a large, talent-heavy region could actually be a better team than the 4th seed (or 3rd) in a different region. Seems unfair that a team that would make playoffs in almost any other region doesn't get to go because they are buried in an oversized pool--these past two years, the HSL's solution is to give a spot to Region 5's #5 seed, favoring them over Region 7 or 8's #4. Of course, the down side to this is that a team that might also have made playoffs loses their spot to a team that they never had a chance to play in the regular season...also seems unfair.
Not sure how to be "fair" to everyone--seems nigh impossible to balance out region size, talent, and geography all at the same time--but winning state isn't the only reason for going into the postseason; teams measure themselves by whether or not they make playoffs and how far they advance, not just whether they win the championship; there are many levels of accomplishment and pride between the state champion and why-bother-trying.