Universities should be more than toll gates

This is also true for universities in Europe and America.

For private universities in Europe it is true. For public (state owned) universities much less so. This is simply because public university does not look on student like on a customer who put some good money on the table to get the final paper. While private universities do.

This is also a reason why in Europe when you have a diploma from private university, nobody really takes that seriously and looks at you like you would be showing him diploma from University of McDonalds.

Yes, German universities don't do entrance exams, there is also no grading on a curve to artificially weed out students. What they do instead is just simply have really difficult exams with a failure rate of 30% and higher for first semester students. The linear algebra exam I passed had a 50% failure rate and most passing students got something equivalent to a D in the American system.