They worked well for the very limited purpose for which they were designed: to shuttle troops and supplies to shore. They weren’t designed as a primary transportation mode but as somewhat of a ferry pretty much designed to go one way: from ship to beach. They certainly weren’t designed as tourist attractions to transport children and the infirm — but to transport trained soldiers and marines into battle. They were designed to last long enough to supply beach landing troops in combat.
It’s like using Spitfires to transport school children.