My FI and I are paying for almost all of our wedding. Originally our guest list was 190 people. My family is 100, his 40, rest are friends. His mother now has 40 guests that she wants to add to the list (making 230) because she feels that since my side is so much larger she has that right. We had to limit our guests to aunts/uncles, cousins, no extended family beyond that since my family is so large. These 40 guests that she wants to invite are her friends, neighbors, and coworkers. She keeps saying that we shouldn't care because after they all give us a wedding present we won't loss any money inviting them.
I personally think she's being ridiculous, but Idk if I should just bite my tongue and invite them to avoid getting in an argument. We have a great relationship and have always gotten along. I should mention that his parents have agreed to pay for the DJ and rehearsal dinner, but we are paying for the rest.