Are all of these apps only available through Google's Play Store repo, or are any of the available as an apk file directly from the bank's site? For some reason most companies only distribute their apps through Google and Apple's repos. People shouldn't have to have an account with and agree to a third party US company's ToS just to download a banking app.

Why are Google Play Services required?

Genuine questions - I'm not from Switzerland and I don't have a Google account.