Multiple end receptacles in one room

There is a junction box where the feed is split and goes to each of your "end" outlets if they are on the same circuit. If they are on different circuits, they could actually be end outlets for the two circuits.

What you'd have to do is install a separate GFCI outlet at each location. Check all the outlet boxes because you might find where the feed splits and you could install the GFCI outlet there.

Older homes are regularly wired in a spider format as the wiring is punched up from underneath or down from the attic. This is different than normal daisy chain used in new construction. There is no right or wrong method as long as the splices are in boxes, Proper wire size and type for the job.

The layout is usually whatever is easiest, so it is quite common to have multiple end receptacles per room if not all of them in an older home that has had wiring updates.

For homes with multiple taps from a single feeder, GFCI breakers are less expensive as only one will be needed for the entire circuit. Where a single room may have 4-6 and there may be multiple rooms on each circuit.