Or maybe it&#x27;s just hard to change what people are already used to. Switching from sugar to sweetener can take over a week of drinking a beverage every day before your brain finally starts liking the sweetener more than sugar. It&#x27;s much too long for people - &quot;trust us, you&#x27;ll like that in a week&quot; doesn&#x27;t really work as a sales pitch.<p>Doesn&#x27;t mean companies don&#x27;t try though; in my city (Kraków, Poland) there were already several Coca-Cola campaigns trying to switch people to Cola Zero. One of them included disguising cans of Zero as regular Coke, attempting to show people that they probably won&#x27;t even notice the difference if they don&#x27;t know they&#x27;re drinking a sugarless coke.