I have stopped giving any lab at the off leash spot treats. Other dogs may get lucky if they are polite and their owner agrees. But no labs! I am using mostly cooked liver as treats these days and the labs can smell them from miles away and will come running up to me and very often just tug at the treat bag. They are very persistent and I have to completely blank them for a few minutes (while their owners call them in vain and get all embarassed) before they finally give up.
But yesterday I saw the ultimate example of just how food obsessed they are! There was a woman walking 3 labs or lab crosses. One of them came running up immediately when he smelled the treats and tried to grab the treat bag. I ignored him until he went away. The other was a pup and didn't know what was going on. The third one was old and completely blind.
The blind dog walked straight up to me - from about 20 metres away across the grass - and walked straight into my legs before lifting his head to sniff out the treats!
I couldn't resist, I sneakily gave him one and off he trotted following his owner's voice.