Player Deplacement when exiting Minecart and Boat

When a Player exits a Minecart or a Boat, they appear not next to where the minecart or boat is, but up to 5 blocks away, which regularly leads to placements outside tunnels in caverns etc. and not on the railstation or landingplatform...
This only seems to happen when there is a suitable space for spawning into, but spawning underwater seems suitable.