maybe the concept of sneak attack is just mind boggling to you
compare 2 senarios
1: ranger on orthon, rogue on fire ele
ranger gets 10% speed, FE damage on orthon, rogue gets nothing on ele
2: ranger on ele, rogue on orthon (ranger with or without FE)
(a) with FE
ranger gets 10% speed, FE on ele, rogue gets SA on orthon
(b) no FE
ranger gets 10% speed on ele, rogue gets SA on orthon. take note that FE is about +12 dmg when boosted by 10% = approx +14. whereas SA is about +30 to +50 (race dependant. in short dps by sneak > dps by FE
or maybe thelanians just suck at the game mechanics