Earlier quoted context omitted.
Copyright includes exclusive rights to determine use and distribution of a work of art. That means copyright owners may determining how their work is distributed, including requiring the bundling with other approved works for combined consumption.
Sure, but drive-by contracts are not enforceable. You'd have to present me with the terms of use and let me agree to them before showing me the content.
Copyright itself isn't a contractual agreement, even though a SaaS TOS may lay out copyright agreements. Websites typically list their copyright publicly, and claiming negligence (typically) isn't considered a valid defense to infringement.