@leasedaudi - it doesn't matter how smart the accountants are (the top FLP bots all use the same firm) if the bots will be reckless and profligate with their company's cash.
They could pay themselves a wage, and have NI and PAYE income tax deducted. They could also wait until the end of the reporting period, declare a profit, pay corporation tax, then issue themselves a dividend.
However, neither of these methods fits in with the instant gratification/overstated real rewards world that they live in.
Therefore, probably against the prudent advice of wiser accountants, they siphon off money as director's loans, which they proceed to spunk on showy expenditure.
They have no real business sense, and imagine that their income will continue to grow, making it a doddle to meet any future liability.
As @Cacacoisfarraige says, they are merely deferring a large tax bill, one that will be all the more hard to swallow once the loan is growing year on year and income is actually falling.
The end result is inevitably that the company becomes insolvent, and they personally end up with a large tax bill that they cannot repay. I believe Insolvency/John Lewis Bot's paltry Bonus cheque this year had already been earmarked for the creditors (HMRC) before it had even been issued.