In my opinion, the coffee cup owners aren't respecting others in the park. They just don't see what they are doing as wrong yet if a youth's dog ran up and jumped up at them trying to snatch a treat it would be totally abhorent. Yet when Phyllis the 5yr old Border Terrier does it, its either not noticed or just midly amusing.
Dominance theory is an outdated view of dog behaviour that became popular in the 1960s. It has since been disproved, evidence having been accumulated that shows that it is unhelpful and often very destructive. Unfortunately, some trainers still cling to the idea, reluctant to let go of something that they have based their training and careers on.
When you read of incidents involving dogs attacking humans, adults or children in the newspaper or hear of it on the radio, that attack did not 'just happen'. Things lead to that exact moment in time where that dog took life into its own control. If you look at any of the dogs who have killed or attacked an adult or child and you were able to look at its lifespan, you would find numerous incidents and triggers.
Nearly all young professionals are now living in small city flats and apartments, but this clashes heavily with dog-lovers' need to have their own pup. That doesn't mean that having a dog is completely out of the question, but there needs to be some careful thought on what kind of dogs are suitable for small spaces.