Passenger Ship emoji is a picture of a huge board which can accommodate a lot of people at once — unlike the one represented by 🚤 Speedboat emoji. This type of 💦 Water transport is often used for sea and river cruises — especially in the touristic areas. So no wonder that in addition to the context of 💦 Water transport in general, this emoji often appears in the context of tourism too.
Examples of using
“My first river cruise starts today 🛳️”
“All ships make me seasick 🛳️”