That's definitely not true everywhere. In many places all over the world, it's not considered stealing unless it was done with the intention to take and not give back. Fx, if you borrow a pencil from a friend and accidentally pocket it, that's not stealing.

Of course, depending on how good of a liar you are, no one can prove your intentions, but you can do some things.

The most important thing is that you need to have enough cash to pay for whatever you're grabbing. If you're only stealing one thing (like in OP's case), and you say you left your wallet in your car and absentmindedly brought along the whiskey as you were going to get it, then you need to be able to go to your car, get your wallet and come back and pay. Nobody realizes they don't have the money to pay, and then accidentally take the whiskey with them. It also doesn't work if you build on the excuse, fx, "oh that's right, I left my wallet at home" and then when you get home: "oh, that's right, I spent my last money yesterday". The first excuse is waterproof, or it's useless.

If you're doing the stealing/paying combo, where you fx buy a six pack of beer, and "accidentally" put the whiskey in your bag, then you need to have your wallet on you and be willing to pay for the whiskey, as well.

You also need to be a good actor. If you get nervous or panic, then you need to abort the mission, because you will look super alert. You're not absentminded when you're super alert. That's obvious. When you leave that store, you trick yourself into thinking that you are leaving with a good conscious (which having the money somewhere also helps you greatly in achieving).

But if you live in a place where it's still considered stealing if you actually did absentmindedly take something, then you need to be able to not get caught, and that's a whole other story.