I've tried to prevent Chrome from starting up when I reboot my mac. There is no setting in the chrome settings to prevent this, It feels like Chrome is a computer virus, infecting my computer and ignoring user preferences. I tried this but it doesn't work:
1) Start Chrome
2) Right-click the Chrome icon in the dock
3) Uncheck "Options > Open at Login"
In System Preferences, go to Users and Groups
After doing the above steps when you restart your computer, make sure you unclick "reopen windows when logging back in" as shown below. When I didn't do this step Chrome opened right back up upon restart, even though I had completely closed out of it prior to restart. you only have to do this once not every time you restart your mac.