I am an academic mathematician, and one thing I love about our culture is that transactional relationships are considered perfectly okay.

I can invite a colleague at another university, whom I might consider an old friend even though I haven't spoken to them in ages -- to come give a talk in my department. Very often they'll agree to come; we'll roll out the red carpet for them, and they and I will have a wonderful time.

That said, this is far from universal in academia, and many academics do enjoy small talk and prefer to keep in touch regularly.

I don't think any sort of relationship can be called "bad" or "good" in the abstract -- but a lot of people consider transactional relationships "bad" in the sense that they don't like them. And, if you want to build relationships with people, often you have to do it on their terms, or at least try to meet them halfway.