It’s difficult with Bane because as FR accumulated other fiendish entities from the larger D&D multiverse, he got progressively less fiendish to occupy a different niche.
Older TSR material portrays Bane as somewhat of a Sauron analogue. He has fiends and dark forces at his command, and his worship entails sacrifice and other sort of black magic. Back then, Asmodeus and the Demon Lords weren’t as prominent in FR, Bane filled that narrative need.
The Sword Coast Adventurer’s Guide portrays Bane as a power of strength and tyranny, the more acceptable face of the Dead Three — his followers hunt folk bandits and commit atrocities, but it’s all for a “greater good” purpose, namely law and order. Peasants may welcome the Banites’ tyranny if it saves them from the depredations of orcs and gnolls.
I think the SCAG’s interpretation of Bane wouldn’t do sacrifices; it doesn’t fit his description and the world’s reaction to it. Those Banites would do harsh executions, mass trials, and other fascitic stuff, but not sacrifices and occult black magic.
As usual, I think this is a DM-dependant question.