Why didn't you think so? I think it's normal for Barcelona to win at Camp Nou, especially since this match isn't a domestic match which has lower prestige than the UCL. This is the Barcelona I know, not Barcelona who could only win with 1 goal like in their previous match when they met Mallorca or could only get a draw with 0 goals when they met Athletic Bilbao.
Barcelona did what they had to do yesterday, in fact Napoli are not as strong now as they were before, and the odds 1.75 for Barcelona to win were a little confusing. I will even say that Napoli was a little lucky that with just one shot at the goal, they were able to score a goal, and play a draw, thereby avoiding a loss in the home match. But after the first match it was clear that the return match would be much more difficult for them.