Band-Aid backing in Sangria

We had a Sunday Lunch at this restaurant on sunday 20 May as a special treat.

We ordered Sangria to accompany our meal. When we finished the chopped fruit in the pitcher as 'desert' - we found paper backing that looks like the paper from a Band-aid plaster. When we showed this to the waiter, she didn't want to touch it. We had to pay for our meal and then she took it to the manager.

He said he would ask his staff, disappeared for a minute or two and came back with the response 'I don't have plasters in my restaurant' and that was the end of it - it was made clear that we must have brought the offending item in. When you pay R450 for a meal for 2 I don't want plasters in my fruit, what else have I eaten? Will a finger nail and the like also be the customer fault? I feel nauseous just thinking about this. Will not recommend this restaurant to anyone. You might be consuming more than you know.