Frankly, I have tied my dog up and gone inside a store . . . though I can see her the whole time I'm in the store, which is why I go there, and tie her to that particular tree. Why? Because 1) I know the neighborhood, 2) I am gone just long enough to pick up a jug of milk 3) I need to go the store and I'm walking there and 4) She enjoys the walk and will be terribly disappointed if I don't take her and 5) the store's owner is watching her too. Because she can't go in the store, I am forced to either leave her behind and deny her a nice walk . . . or tie her to a tree for approximately two minutes, about 15 feet from me.
Now, would I leave her tied up somewhere while I went to play golf . . . no. But I know people who would . . .mostly because they haven't thought about what could happen. But I'm not going to condemn the dog's owners on this. They were on private property, they had permission, they presumably knew the dog well enough that they were pretty certain she would not cause a problem. Wise? No. But I don't think its quite fair to scream irresponsible owner at them . . . more like naive owners. I'm sure it is not a mistake they will ever make again.