As explained in https://www.reddit.com/r/leagueoflegends/comments/66w5uc/disable_scroll_zoom/ :
Edit this file:
C:\Riot Games\League of Legends\Config\PersistedSettings.json
After the "shopEvent"block, to add this 'MouseSettings' setting
The totem ward will give your team vision, but a control ward will give your team vision and it will deny the other team vision.
Denying the other team vision is really important when setting up for objectives (Baron, Dragon) or when pressuring different lanes. If you're sitting in the top river, and the other team doesn't have it warded, the threat of ...