I talked with a professor for possible thesis guidance and mentioned that I aim to publish papers at top venues as soon as possible.
One can only speculate, but maybe the professor was annoyed by your usage of as soon as possible more than by your intention to publish (if this was indeed what you said to him in verbatim). Maybe he inferred from this wording that, to you, PhD school is an unnecessary nuissance that you expect to leave behind you quickly, so that you can go on to greater glory.
I think in general a professor should really not be opposed to you publishing in good venues on principle, as this would mean that his students are basically locked out of an academic career for good - and which advisor would want that?
To answer your titular question Is being publication oriented bad?:
Yes, if it means you do only "easy" incremental research in order to minimize risk. No, if you just mean that you do not only want to do any research, but are actively looking for topics that are publishable and which will have an impact on the scientific community or, in some cases, industrial practice.