Every store branded Gift Card is only for purchases at that store and not redeemable for cash. Prepaid VISA cards are not a store branded card and is equivalent to a Debit Card.
The Steam Gift Card you refer to is only for Steam products.
Steam Gift Cards work just like gift certificates, which can be redeemed on Steam for the purchase of games, software, hardware, and any other item you can purchase on Steam.
https://store.steampowered.com/digitalgiftcards/
For the Razor Gift card, this is what they say:
You can only redeem your Razer Gift Card on Razer.com (US Only). Not valid for use at any physical retail stores, including RazerStore San Francisco and RazerStore Las Vegas
https://www.razer.com/razer-gift-card?srsltid=AfmBOookCMaED31guWG4opd-N13UWG-uTWajP3JWSuZoxX44OrOI7-ET
Similar to the examples you provided and also with every other store branded Gift Card, you can see here what can be purchased with the Apple Gift Card. You will see that it can be used for purchases on any item at apple.com as well.
What you can buy with your Apple Gift Card or Apple Account balance - Apple Support
Specifically to avoid Apple Gift Card scam, Apple does provide this helpful support article:
About Gift Card Scams - Apple Support