Family dinners- 2 part question.

We've been doing weekly dinners with my in-laws (mil and bil) since hubs and I moved in together 8 years ago (when he moved out of his mom's) we alternate weeks, her place and ours. My bil has lived with her most of that time, but even once he moved out doesn't host. This has never bothered hubs and I, mil has made a couple comments so he's hosted once a couple years ago.

Now he's moved in with his girlfriend and her two children (7 & 8) and has started bringing them for dinners too. He did ask to make sure we were okay with that. And for the most part I don't mind, they're nice and I like getting to know them. But the cost of dinner has now gone up ( we also have a toddler)

So my questions :

1- Do you think it would be okay to approach them about maybe joining the rotation for dinners? I don't want to be cheap, it's only 2 dinners a month.

2- What are some good meals we can make, that make a lot of food but are cost friendly

* Side note my province is allowing us to have close contact in 10 person social circles, so we're still social distancing *