Agreed. I can't imagine trusting it enough to make a purchase automatically, and that's before getting to the reality of how awkward it is. Which brand? Which quantity? Which style (extra strong, extra soft, etc)? Did the price go up since last time? All stuff that you can visually spot in a half second, but would be a huge PITA verbally.
And it doesn't help that Amazon often doesn't have great pricing on bulky, often fairly low value, consumer staples. (And, in my case, I have a Walmart just down the street so I'm not going to order my Bounty or Charmin from Amazon. The case may be different if you live in a dense city without a car but that's not most people.
That AI is clearly a product imagined by wealthy tech executives who have personal assistants who shop for them, who trust those personal assistants to buy what they expect for them. The use case doesn't resonate for us normal people, because we do our own shopping, are price sensitive, and typically don't just buy things without doing basic research about what they cost.