You literally just told me off saying it has nothing to do with anything though it was part of the context, and you tell me I'm harsh. The nature of context is it does not stop existing just because you don't mention it.

I very much agree it's exactly organizer's duty to write visa invitations, and without prejudice and discrimination, and if they want they can do other things to combat abuse as I suggest.

Whereas your idea that "it's not his(sic) job to do anything" is very dubious on many levels and no offense I hope I don't have a misfortune to attend a conf you organize :)