Strictly speaking, they don't get the atmospheric braking for free...still needs a heatsheild and guidance system; but they don't have to drag extra mass of fuel, rocket engines, etc with them during the ascent part of the flight...which adds up REALLY fast. Look up "the tyranny of the rocket equation".
odddutchman t1_j5w958r wrote
Reply to comment by electric_ionland in Why do sample return missions such as OSIRIS-REx use their own reentry vehicles instead of just going to the space station for pickup and return with ISS equipment? by PromptCritical725
Strictly speaking, they don't get the atmospheric braking for free...still needs a heatsheild and guidance system; but they don't have to drag extra mass of fuel, rocket engines, etc with them during the ascent part of the flight...which adds up REALLY fast. Look up "the tyranny of the rocket equation".