Using this new feature doesn’t turn on Chrome sync. And of course, if you prefer to save your payment methods only locally on your device, you can still do that: Add your card in Chrome Settings > Payment methods > Add. When you sign into any Google website, you’re also signed into Chrome with the same account. You
can turn off "Allow Chrome sign-in" altogether in settings.
Every time you open your browser, you have a task in mind to accomplish. We’ve built Chrome to help you do that as quickly and safely as possible, whether you are completing a search, viewing a website, or making a purchase. This feature is just one more way we are improving this experience for everyone.