In reply to Miroslav Glavic.

You:
You (and everyone else) have no right to enter any country outside your country of birth.

A statement generalized to the extent that it's completely untrue. EU says (example):

For all EU citizens, citizenship implies: the right to move and reside freely within the territory of the Member States (Article 21 TFEU) (2.1.3);

And not true for the many having sole citizenship in a country they was not born, like legal immigrants, born when parents were temporary residing outside their own country, and adopted people.

"Country of birth" define rights, in most cases, but by far not all.

For non-Europeans, the primary criteria for being allowed should be that they have the necessary means to support their planned stay. The ticket price should be irrelevant, even when unusually low for a professional conference.

I guess, by your last statement, you are trying to insult some people.