Why not both? A big part of dating is increasing your opportunities to meet someone.

Plus, asking out strangers is lots of fun. The uncertainty that comes from stepping outside scripted social interactions creates tension. And tension what sexual attraction is made of, if you can remain calm and have fun with it.

And while it doesn't have the highest chance of success, when it lands it creates this feeling of stars crossing. Two strangers make eye contact and are immediately drawn to each other? Who doesn't want that 'how'd you two meet' story?