The contract is indeed real, it's just that a different method was used for accounting. If this money was really made, eighty-five percent of it would all go to Old Tang.
The remaining fifteen percent goes to the law firm, taxes and management fees and all that included.
So you can understand why every time Old Tang fools around outside, Old Wang would be cursing there…
Old Tang doesn't take a penny, so the bulk of it is saved. The law firm, on the other hand, has to settle the remaining accounts, and at the very least, you have to do the taxes properly.
Of course, compared to the benefits brought by Old Tang, this amount of money is actually not much. If there's a problem, it's the suspicion of providing free legal services in violation of regulations.
But if the Lawyers Association itself thinks there's no problem, then there isn't one, especially since there are indeed many lawyers who do pro bono work.