Exactly. More brands means a bigger chance to find a good deal

He does.

Not copying the rewrap (Vapcell) company.
Just Vapcell rewrapping Sanyo and then sell it as their own. That way they make some cash instead of only Sanyo.

I can imagine there is a profit in it. Numbers as a way of explanation.
Sanyo sells cells for $2/each.
A famous company rewarps them, adds some marketing claims and sells then for $10/each.
Then a copycat rewraps the Sanyo’s with the same wrap and sells them for $5/each.

Or even more illegal, buy junk batteries at $0.50/each and then rewrap and cell as something good and famous.