Honey traps can be used for many other purposes than just obtaining pillow talk.
The spy can place electronic listening devices once they have access to different locations.
The spy can use the person as an introduction to other folks with access to intelligence.
The spy can rifle through documents if they have any private time at the location....
Or they can gain personal information other spies can use to track, trick, trap etc etc etc....
Intelligence can work one step at a time and the individual mark may never know their role in the plan.
Yeah... I know. I was being a smartass during a class. It’s a gift...
Blackmail for one. Once you’re a compromised it’s easier to play ball even if the stick is relatively lame, career embarrassment, angry spouse, etc.