Sadly at some places it's intentional so your password matches existing PIN systems or is "easy to remember" so you're not as easily locked out of your account. I wish in those cases there was a check box that says, "I know what I'm doing, leave me alone."

Speaking of annoying validations, my name has a hyphen in it but you'd be surprised how often that's rejected with the familiar, "Please enter a valid last name." Sigh.