The idea behind the 69 Swinger 340 was a LOW COST performance car. So, no console or buckets to keep the cost down.
The Plymouth version is the 1969 'cuda. Low cost, no frills., bench seat standard. But optional interiors could be ordered. I've owned both a stripper and a loaded A56.
In general, the Barracudas had a higher price line than the Darts. It's in the VIN.