In a nutshell, me, dh, our kids, sil and her husband bil and their baby and other sil went out for the day. I took a lot of snacks and food for everyone and got extra things they requested. Cost about £25 that was ok.
Then at lunch I had brought lunch for me the kids and the baby, plus the drinks and sides and bil went to get burger and fries, he ordered himself, his wife, baby and other sil one, my dh then said yes I’ll have a burger and fries too, each of these are £9.50, bil and sil just stood there and dh ended up paying for it.
How the hell does that make sense, you order 4 meals and let the one ordering 1 pay for the big bill of nearly £50. Who even orders a meal like that for a baby, and had already asked me to get the baby’s meal before coming which I did.
All in all they had a free day and we paid around £75.
No thanks, didn’t even finish their food, no thanks at the end- happens all the time.
The couple sil and bil always do this, never pay their way and the non married sil never doesn’t even bring money half the time. 
How can people free load like this
We all work we all have a mortgage bills kids, since when should we keep spending and they save all theirs ???