Some 'enjoy' questioning the McCann's behaviour. Some 'enjoy' questioning Amaral's behaviour. Some 'enjoy' questioning Grime's behaviour. I see no difference, although some believe their behaviour can be morally justified and other's can't.
Sarah Payne did not close her twitter account because she was being asked questions.
Trying to claim there is no difference between the treatment of the McCanns on the internet and that of Grime or Amaral is like claiming there is no difference between Mount Everest and Mount Snowdon, because they are both mountains.
I have never read allegations anywhere that Martin Grime was a narcissistic psychopath, or a lying fraudster or a paedophile - to name but a few of the allegations which are screeched out on the WWW about the McCanns on a regular basis by gleeful 'trolls'. I won't call them sceptics because that would be an undeserved insult to all sceptics here.
If you think Sara Payne closed her twitter account because she was being asked genuine questions by sceptics - and that she was not being persecuted by cruel people who enjoyed spitting venomous abuse at her - then that's not my problem.
Schardenfreud (sp?) is a condition where people gain pleasure from other people's misfortune and is alive and well on the internet IMO.
AIMHO