One of the most irritating things about eating out - apart from being endlessly pressed to order mineral water - is the habit of leaving a gap on the bill for a tip when you've already been charged for service. (Usually 12 1/2% these days)
In the case of Sofra restaurants they don't even go through the pretence of saying the service is 'optional', they charge it and then charge service on the service charge.
There was a lot of adverse publicity a while ago about this and restaurants stopped doing it for a while but in these credit-crunched times they're obviously up to their old tricks again.
So look out for it, don't pay it and let's name and shame the restaurants who do it!