When this was originally discussed, way back
here, we put together some charts showing average expected wealth for characters who adventure and get treasure, and new characters created by DMG rules. Bottom line is that, with a few outlying levels, the two numbers track fairly closely, except for levels 2 and 3, where the DMG numbers are unrealistically high.
We tossed around a few ideas, but finally ended up awarding 90% of the time gold that you would have gotten if you'd gotten to level 2 or 3 purely on time xp, rounded up to even numbers. So, at the end of the day, they're arbitrary numbers that seem vaguely reasonable.
If you re-read that thread, though, all of the discussion was sparked off by someone retiring at level 2 and starting a new character also at level 2, using option B. I'm pretty confident that that's what we all had in mind, the whole time. But somehow, in copying it to the charter, it got put in under option A. No one has ever used option A to my knowledge, and I don't really see it happening.
I think at the very least we ought to clarify that the numbers in question -- 780 at level 2, 1750 at level 3, per DMG otherwise -- apply to option B, not option A. And IMO we should probably get rid of option A while we're at it.