I don't want to talk to salespeople, only product designers, developers, executives, and support staff. They are the people who make the stuff and/or are left holding the bag for the product when the salesperson is jetting off to their next meeting.
Same goes with service contracts for leased business equipment (copiers, postage machines, alarm/security systems) - let me talk to the "support" staff who don't read their own technical bulletins BEFORE I sign so I can decide not to go with a vendor who "requires" full admin rights to my server to manage their copiers.
This doesn't necessarily scale past small-mid size businesses (mine have been up to $20ARR and ~150 people). The occasions I've talked only with sales, there have been broken promises, missed deadlines, and a big mismatch between what we were sold and what we got.