@youronlyone for most Italians #pineapple on #pizza is heresy.
Here's why: a good tomato sauce, made with high quality #Italian tomatoes, provides a level of acidity that doesn't go well with pineapple. If you even consider the taste of a good mozzarella, sweetness coming from fruits is entirely off-putting in the mix.
Pizza made abroad doesn't often have a good tomato sauce and real mozzarella, therefore pineapple can make it better.