The hell you don't sell them and buy yourself a game or two?

do not let yourself be manipulated by the rat people who scam as you see in your comments because they earn money based on that, the cards that the games give you are used to create badges depending on the game some are very expensive and are worth a lot therefore the market exists from steam, if they bother you to have them in your inventory, sell them, but you never listen to them, you never GIVE THEM AWAY the cards those rats just want profit

added to possibly trade some of your cards

You can sell your cards here:
https://steamcommunity.com/profiles/76561199096164013

Please accept request

Adding you!