For most resorts, at the end of the week, you are able to take home your lift pass and keep this as a souvenir, or bring this back to the resort and recharge this for a small discount on your next lift pass
For some resorts like Risoul, it is expected that you hand your lift pass back into the resort at the end of your week. You'll be informed how to do this by an in-app message at the time. This resort does impose a fee of €5 for not returning the lift pass so it's important that this is returned.