The pedestals come complete with receptacles, breakers, meters, etc.; pre-wired with main lugs at the bottom for the feeds. They're 3 wire, two hots and a neutral, connect a ground wire at the bottom and you're done. Can be configured with any type and as many receptacles as you want, also with cable tv, water spigot, whatever you need. As I said they are pre-wired - Each circuit breaker is branched off the 3 main lugs, and wired directly to the three outlets.
The main feeds are generally 250kcmil or larger and are on circuits of 200 - 400 amps depending on the number sites, and number and sizes of receptacles being fed. They just daisy chain the feed from one pedestal to the next, to the next, etc.; just like you would wire receptacles and light switches in your home off one breaker in the main panel.
Midwest makes a lot of them, also Siemens, GE there are others.
That's also probably the best way to put one in at your house. Just run the feeds to the lugs and you're done, no worries about wiring the receptacle wrong.
So in this situation each individual receptacle will give you the amps its breaker is rated for.