Whenever I order coffee from a restaurant, I order Splenda, or "the yellow one" if the proper name for it doesn't come to mind.
There's no particular reason for this. I know there's also a blue one and a pink one, and the newest entrant is a green one. I don't remember why I started using the one that I do, doubt it was rational or evidence-based, and have no confidence that I could pick the Splenda-sweetened coffee from alternatives by taste alone.
But it is useful I think to have a default option, and so long as there is no reason to adopt either of the others, I'll stick with my default.
What percentage of our choices are default choices, made on no better basis than my invocation of Splenda at such moments?