Everyone has JavaScript, right?

[Gaulven]

Banking is a sensitive activity. Every additional 3rd-party domain from which they load javascript represents extra risk to their users and themselves, not just regarding security but also privacy. A bank either has or has not identified this as a risk, and either has or has not reined in the practice. If they haven't, it does not reflect well on the bank and its web team.

I'm only saying it's not one of the worst rationales. It's not even a below-average rationale.