Access. For most people, it seems hard to get a few thousand sats and easier to use their credt card to buy coffee.
another thing to think about is that when bitcoin will be more accessible to buy because more adopted, the actual value of it, will still put a big obstacle to acquire many bitcoin and then use it, so is not even an adoption problem is just about being lazy for many
You really can't call that lazy, since people aren't really educated enough on this subject. Now how do you educate one who does not want to be educated?