So is it every time or just sporadically?

If every time then weird.

If sporadic then perhaps a passive aggressive way of trying to tell your daughter she's overstayed her welcome that day especially of they had fed her lunch. (Admittedly grasping for straws a bit there)

They may be two professionals but maybe cash crunched and overextended a bit?

That’s not odd. That’s fucked up.

Involves my daughter's best friend, or more to the point, her parents. Over the years we have probably bought my daughter's friend dozens of meals. If she's over and we go out to dinner or get take out, or stop to eat on the way home from a game or something we get her something, obviously. And it's not like she wouldn't give us money or at least offer if she went with us to a soccer tournament for the weekend or something similar, but usually it's more spur of the moment, unplanned meals.

I would do that for any kid who ended up with us, but particularly for my kid's good friends, I just figure it will balance out. There are times when my kids will be with their parents and their parents will buy them a meal. Regardless of it balancing out or not, it just seems odd to not buy the kid something so they sit there and watch you eat.

Anyway, it happened not for the first time again last night, where my daughter was at their house and they decided to get take out, but told my daughter she could just find something to eat there in the house instead of buying her something.

And these are two professionals, it's not like they are living hand to mouth.

seems like one of those situations where you absolutely don't want to call it out. Bizarre enough that a friendship could be ruptured, and girls need their besties.