Lawyer here. I've seen B2B contracts like the kind proposed above (the terms as a form attached to a pre-existing contract). They've been a thing for decades;

Lawyer here. I've seen B2B contracts like the kind proposed above (the terms as a form attached to a pre-existing contract). They've been a thing for decades; they're just very uncommon and usually aren't used until the businesses already have a pre-existing contractual relationship. Generally, the integration clause is uncommon in the contracts I've seen; it's used in big-ticket contracts (like M&A) but not so much in day-to-day contracts where friction can kill a transaction.