I'm surprised how hard it is for me to think of a case where including some extra by default makes sense for both the seller and customer. My initial reaction

I'm surprised how hard it is for me to think of a case where including some extra by default makes sense for both the seller and customer. My initial reaction was a mixture of happiness about combatting hidden charges and suspicion that it might rule out some reasonable practices. I opt out of the sandwich drink and chips combo at a lot of restaurants, but most other patrons like it. But after mulling it over, I can't think of any of the latter that would apply to online sales.