What a disgusting user, masquerading as a (now-ex) friend.
I've read a few instances of this (mainly on MN), where some new/expectant parents will ask for very specific expensive baby stuff, often laying on the guilt about how much they need it, planning all along to sell it - whether new stuff to be bought by family/friends or things 'desperately needed' on FreeCycle or Facebook Market Place.
I suppose they see their opportunity, exploiting how keen people often are to help when a baby is on the way; plus, if they can just stall seeing the giver for a few months (or the giver seeing them using that item), they can just say that it was so greatly appreciated, but now that their baby has outgrown it, they've passed it on to a friend or indeed have sold it to use the money to buy next-stage stuff.
That's nasty enough when it involves paying money to buy things from a shop, but when they've deliberately wasted a huge amount of your time in getting you to make it, that's far worse still.
Either way, you know they won't have sold it for anything like its realistic value/what it cost you (to buy or in time and materials); but they don't care, as it's 100% 'profit' to them. Not much different from drug addicts in that respect, really.