More work for the company, and leads to even more negativity in the process.
The negativity may likely exist from no response/lack of feedback -- which can be frustrating for ppl that spent time/effort), but at least as the previous poster mentioned some people do appreciate feedback.
Also, recently noticed that companies have automated questionnaires asking how the recruiting process was or can be improved -- wondering if there's any improvements based on feedback.
As a side, it's been kinda interesting to read glassdoor responses for how people were treated/felt during the whole process (timing, professionalism etc...)
Yes, I can't remember where I came across the data, but providing feedback didn't actually increase interview satisfaction, but decreased it in the aggregate.
Candidates are prone to arguing and trying to nitpick the feedback to get reconsidered. It's counter intuitive, but that's what really happened.