Ahh dooin, I was thinking the same thing. We have a caravan on the coast in possibly one of the 'chavviest' places known to man. We come here most weekends and every school holiday throughout the year. The beaches are all dog friendly and I have never, not once seen a stray dog poo left on the beach.
There's plenty of horse poo, Tons of seaweed and on one memorable occaison I offered a dog poo bag to a woman whose toddler was busy having one at the waters edge ("no, it's ok, the tide will take it" "no, it really isn't, pick it up")
there are tons of dogs here. Every morning and afternoon we run MuttDog on the beach and we see at least 10 other dogs, rain or shine. We've also never seen a dog bite - but have seen plenty of unleashed children running up to strange dogs (MuttDog included, and she's very nervous around people she doesn't know, so could bite in fear)
I know one person who has been bitten. She works as a rescuer and was checking the suitability of a dog for rescue (ie owners said it was good with children and well behaved - she checks if that is true). She was bitten on the arse but at no time blamed the dog. Just the ignorant abusive bastard that owned a GSD and didn't walk it.
I think the no-dogs brigade do tend to exagerate