> Putting more records wouldn't really make sense (you have to delete those records manually to start using the CRM).
I would assume that their point is that this would demonstrate that the system doesn't break down if you fill it with more than a handful of entries. Would be a shame if it grinds to a halt after using it for a few years.
And demo data != initial starting state
We'll work on a real demo environment with a lot of records, we just haven't prioritized it yet. Right now it's not really a demo environment, but a real account that happens to be provisioned with a few example records. Putting more records wouldn't really make sense (you have to delete those records manually to start using the CRM).