It is quite common to say "We had a meal" whether saying it was for one person or for two. Suggesting that's the "smoking gun" to prove it is a comp is really grasping at straws.
There is no doubt that at one point TPG did accept comps. They say they're not doing that now. And the common belief is that the site is making plenty of cash through CC affiliate links to be able to afford things like that meal. Especially after calling it a business expense and knocking 30% off the price.