I usually carry according to the event. Many of my events involve beer. So, I pack a SAK to those events. And yes I will loan it out but I always open and close the blade or bottle opener. Usually, I am the initiator, "I have a pocket knife if that will help...". Or, "here, let me help you...". If you hand it over, open, most of the time they hand it back open.
Today, casual Friday, jeans I have a mini-griptillian. Having a hard time opening the coffee bag, here let me get that for you. And since it is a "big" knife in some sheeple's eyes, I keep it mostly hidden in my hand.
One time, I was watching the some of the neighborhood boys playing football (7-8 yo). Standing next to me was a mom and her little one. The child had one of those huge plastic pixie sticks that the sell at the concession stand. It was all gummed-up. I offered to cut the tip off. She said that would be great, then I opened up my SOG Twitch II (assisted opening) and took care of the problem. But, I get the impression the knife startled her - switch blade? - in her eyes. Not to self to be a little more subdue...
At my fire-pit, when the neighbors pull up and the kids are running amok - in a good way - you'll often hear, ask Mr. Tim, he always has a knife on him, he'll help you.