This post is full of incorrect or (at best) very dated information.
So far your only option is to find one of those services which offer btc debit cards but they don't work as simple as you want them to be.
You need to deposit bitcoins in them first and they're debited as dollars at the current price and they you can use it. And yes you need to wait for confirmations and stuff like that but the balance becomes available later on.
I've used one similar service so far called Advcash but they don't issue real plastic cards. They give virtual cards. So they send you your name, card number and the cvc. I've used two or three times to buy gift cards online (just for testing though) but I heard that amazon and other sites don't accept them.
Not true. There are several options that do not require the card to be loaded (prepaid).
"I've heard..." is not advice. You shouldn't post about hunches unless it relates to the future price bitcoin.
Wait what ? Take directly from the wallet ? Of course impossible. This means that somehow the service that issues your card should have total access to your address with private keys ??
Not a good idea.
Sir, are you not familiar with bitcoin exchanges? Most of these debit cards only work through exchanges...so wallets where you don't have any private keys. Bitwala works with Trezor but you do get the protection provide by MasterCard or Visa.
You have to keep the coins with the provider. Most of them convert all of it when you deposit. Of the ones I've messed with Xapo is the only one that keeps it in Bitcoin and converts each individual transaction so you can carry on appreciating the rest.
Shift now does the same via Coinbase. Bitwala draws direct from your bitcoin balance too.