Don't know where you're all from but I live in Nottinghamshire, and a lovely place for a walk is Clumber Park, which is where I went with the OH and dog on Bank Holiday Monday.  Having walked for about, ooh, ten minutes, were decided a well earned sit-down was in order so sat on a bench, overlooking the lake.  Toby sat happily until another dog came along, and refused to leave him alone.  This other dog of course was off it's lead.  One of them began yelping, and Toby was pulling frantically at his lead.  I turned to see two young girls sniggering away and they very nearly got the rough end of my tongue, as naturally I thought the dog belonged to them and they were doing nothing to get him away.  As it was it belonged to another lady, casually pottering up behind, who unfortunately DID receive the rough end of my tongue, when I asked her politely but rather firmly to 'call your dog away PLEASE'.  I do realise that most well trained dogs are wonderful off their leads, and of course Clumber Park is a lovely place for them to have a run around, but this woman surely should have had more sense than to let her dog wander off a good two minutes ahead of her, and she should have called her dog away immediately as she could see I was struggling with Toby, calling him to stop pulling etc.  Makes me really mad - she just didn't have a care in the world. 

I can completely sympathise with you!! Some people are just born inconsiderate!