Why would Chad Loder take advantage of them? Yes, it gives him the
ability to, but that doesn't mean he will.
Why have security? So some random, untrusted person can't compromise the account. If Chad holds the codes, then only he can compromise the account, and maybe their relationships are good enough that they would trust him.
Using a different email provider also works, but I assumed there would be some reason that doesn't work - android effectively has a built in gmail client, non-tech people might just autocomplete "@gmail.com" and mess up someone's address if it is a non-expected domain, etc.