In Europe they write numbers a little differently than here in the States. Add to that a particular individual's poor penmanship and what appears on your restaurant bill could be even more confusing.
Such was the case at a restaurant in Istanbul a few years back. We ordered two entrees and some beverages which totaled 41 lira. However, the number "4" looked nothing like a "4" and instead, looked exactly like a "6" (I wish i could post photos here to show you what I'm talking about). I handed the waiter 70 lira and started to leave, treating the extra 9 lira as tip on what I thought was a 61 lira bill. The waiter gave me a strange look and paused for a moment before heading back into the kitchen. It was only after I left that I thought what an expensive meal that was. I take full responsibility for not looking at the individual items and adding them up to check the total, but surely the waiter must have though something was wrong when a tourist was tipping him 29 lira on a 41 lira bill (70%!!).
I don't consider this a "scam" by any stretch but as a reminder to you all, DO read and re-read the numbers and perform a sanity check on the order of magnitude of the totals in relation to what is considered reasonable.
On the bright side, the food was in fact, very good though.