I was at a Buffy con in 2001 and it was a free autograph from all the guests...but entry was a lot more than the £15, it was about 3 times that 16 years ago. So we paid up front rather than person by person but someone has to pay the guests or they don't come. It's not charity. They don't owe you the experience.
Were you at any of the Nocturnal cons? I went as one of the Gentlemen from Hush and my girlfriend and mates came First Prize in the costume competition as the Hannah-Barbera 'Scooby Gang'!