No, cultatrad does not have any membership fee and you can cancel your account anytime.
If you miss home food when you are away from home then cultatrad is the best platform for you. Students can also support their living, pocket money and pay college tuition by being cultatrad host.
Yes, some hosts do offer documentary, games, language sessions, etc. along or without cuisine session.
Restaurants serve food as a part of business with their business model and targeting profit. At cultatrad you will have an experience of taste from people who cook food for fun.