Would it be acceptable to report a professor for poor teaching / attitude in a Masters graduate course?
You should discuss this situation with your department graduate chair or a similar authority.  It is important to give your program feedback so that they can improve.  However, keep your feedback constructive.  The word "report" is excessively negative.

I think you should adopt some perspective.  Often, graduate level courses are not treated as seriously as undergraduate courses because graduate students are expected to spend their time on independent research, not course work.  Also, while you may be paying a lot of tuition, it is unlikely that an adjunct professor is receiving very much pay.  Many adjuncts are working many jobs to pay their living expenses.  They often receive no training from employers.  Poor teaching by adjuncts can reflect problems with the structure of the institution rather than with the individual adjunct.