Unfortunatley there are some mean, clueless people in this world. Your story reminded me of my good 'ol step-mother. When I was in my twenties my dad remarried. Bea (step-mom) had twin girls my age and a son. We were never invited to "her" house when her kids were there. And when we were, we were treated as "guests". Even at Christmas and holidays she kept us separate. My sister and I laugh now, about how we got the bargain bin gifts. And, we graciously received them. Bea would buy me, my sister, and my brother's wife all the same nightgown from Ross Dress For Less no doubt. We wondered, but never knew what her kids got for Christmas. It's not like money was an object. My father was quite wealthy. I remember one evening after my new husband and I had moved into our first home (back in '83) we invited Dad and Bea over for dinner. They drove up in their new Mercedes and she was so kind to bring me a house warming gift. It was a $2 plastic potted plant from K-mart! Again, I graciously accepted and thanked her for her thoughfulness and threw it outside for the dog to play with as soon as they left! Ahh fond memories!
Perhaps your MIL in some way must be angry or jealous of your relationship with your husband.
There is no nice way to tell her she's a complete idiot. No one is that stupid. She is totally intentional. (I used to think that Bea was just stupid). She was sly like a fox.
If you or your husband were to bring this to her attention, she would be in total denial. She must be a very controling personality. Don't let her have any control over your emotions.
When she gives your daughter a gift, tell her to accept it graciously, and then throw it to the dogs! Then go buy your daughter something special. It will make you feel better anyway!
Of course, that's not teaching your daughter much respect. Okay, what you could do, (it's not as much fun) would be to rise above her level. When there is a time for gift exchanges, buy her something absolutely wonderful and thoughtful. If it's important to you, win her over with kindness.
It may just drive her crazy....
Good luck and God bless