Yes it does but you might have to change it in the settings. SwiftKey is by far the best keyboard available. I have been using it for years on several devices. I'm typing this on my tablet with SwiftKey. There's a lot of customization with SwiftKey and plenty of help. The keyboard is so popular they have there own forum.I liked Samsung's keyboard because unlike Google's it is smart enough to know not to put a space after '@gmail.'
Does swiftkey have that built in too? Entering forms on Google's keyboard is so painful.
For other 3rd party kb's I'd worry about that, but not with Google's. The card I mostly use Google already has because it's tied to my Play Store account.
Trustworthy ones though (Google Keyboard, SwiftKey, Flesky, Swype, etc.) won't do anything of that nature though. It would have been found out by now. The permission just means they could see it (which makes sense) since it would be used for the input. I know with SwiftKey at least they have predictions shut off when you enter a PW field (no words above the keyboard when typing in there).