My mil does this and I see it much mentioned on MIL threads.
My MIL is always buying new clothes for the dc, sometimes she gives them to us sometimes not. I can tell she is slightly irked when she sees I have brought new clothes for them. The dc will often come back in new outfits and any pics they send to us from their house dc are in different clothes than what I dressed them in.
I personally have long issues with MIl and fil, but I just wondered what is it about this specific issue of clothes that other posters find odd?