You can only use your Steam Wallet gift card to purchase items. Any associated value can be used to purchase video games, in-game items, software, and hardware. Each digital card comes in denominations of $5, $10, $25, $50, and $100. In addition to physical stores and online store transactions, Steam cards can be purchased digitally. In addition to purchasing physical cards from a store, you can also gift them or order a card and send it digitally. The Steam Gift Card and Wallet Code are just as valid as gift certificates, which can be used to purchase games, software, or any other item on Steam. If you are looking for a place to purchase a steam card, your best bet would be to look at a grocery store or a place that specializes in selling gaming items. This is because steam cards are not a common item that people purchase at gas stations. Most gas stations do not sell steam cards.