Looking for a power centre compatible with 240v breakers

Chris Bryant wrote:

That's my question- you will not find a 30 amp 240 volt hookup in a park, so you will have to use a 50 amp plug.

If this 30 year old rig ever sees a park I'll make up a dogbone. Even if I upgraded it to 50amp, I would still be using 50amp twist lock, which you would never find at a park anyway, so I would still have to make a dogbone. Why would I want to add a 50amp breaker and larger, heavier, more expensive shore cable which will never come close to being used at full capacity?