spare a smile

So I was out with my girlfriends for a round of cocktails and ended up walking along the bike path on Santa Monica. We sit down for a minute to cool off the alcohol + semi-exercise when a homeless looking more LOST [mentally or physically] than actually homeless stops in front of us. "Sorry, I don't have change" is about to roll out from my tongue when the guy says, " can you ladies spare me a... SMILE?" We sit frozen, speechless, for a second or two and smile up at him. We smiles back, thanks us and walks away. I feel horrible and despise myself. I can't believe that the first thing that would pop into my mind when I see someone like that approach me is sorry. Shouldn't it be something more like, " Are you ok?" or " Do need some change?" Honestly, giving them a dollar or two is not going to kill me and definitely won't need the change later.