Yes she has two use cases, first is fast clearing your inventory for stolen items after stealing endeavor.Interesting as my impression was always that the penalty was there to avoid "pay-to-win" complaints because she was only available through paid content. This way the base game fences are better.
But actually the logic of avoiding heat does make sense to me, even if you can also obtain a home to easily do that. Gives two different methods.
I almost never used her originally but since I am a long time player with a decent amount of gold, combined with the quick slot update so she can be in the allies section, I do use her now as clearing inventory quickly is one of my top priorities.