Its what you have to expect of university lecturers. Apart from the very few who are in the Economics/business school who may have a more neoliberal view, most are either very left wing, or too scared to come out as being anything even slightly to the right of center.
That said I am not saying people cannot have their own views, but university should be a place where people expose themselves to new ideas and concepts and lecturers/seminar leaders/tutors should be encouraging this, not as you say only allowing the discussing (what I imagine are only the good aspects) of one viewpoint. If this isn't the case then you are just hearing what your side (be that left, right or center) says and aren't really learning anything new.
Honestly I think outside university all sides are just as guilty of this, however it does seem to be more the case that those who are left wing want to stifle and silence conflicting views more than right wing people and that is nowhere more evident than universities.