Do the math. At $2.00 a gallon, 10 cents difference is only 5%. League Operators charging from $5-$11 is 120% difference!!! It's just too much of a discrepancy, considering when you get to the regional or National level everyone gets the same amount of price money. You'd think the main office of APA would set guidelines for fees. Anyway it's just an opinion.
Doing the math by percentages isn't really a fair way to compare. League fees are usually set in one dollar increments (every league, not just APA) per player, so when there's a difference you're comparing $6 to $7 (17%) or $7 to $8 (14%), etc. Maybe one day when there is no more cash and everyone pays for everything electronically, there can be more granularity in fee structures, but for now nobody wants to make captains collect $6.32 from each player.