Speaking from experience, it's hard accepting gifts when times are tight and there's no way we/I can reciprocate.
For me, I've learned that the best gift I can give in return is to be gracious and accept them. The pleasure is in the giving. Gratitude is often all the giver really wants.
If you still feed the need to assuage the "obligation" you feel to pay it back, pay it forward, in whatever means you can. Give to someone less fortunate than you.
What is your position in all this gift giving relationship between your husband and his other? I would consider stepping over bounds to "veto" gifts to your husband. But really, this is an issue between you and your husband that needs to be discussed and an agreement that both of you can live with needs to happen. Otherwise its only going to continue to cause problems.
As for gifts to you and your daughter, I believe you have every right to not accept the gifts. Your really have no relationship with her other than you "know" the same person. You have no obligation to become her friend. There's no rule in the Poly handbook that says you have to.
IMHO, she's trying too hard to make a friendship with you happen, and that's a little worrisome. Her intentions may be good, but she really needs to slow down.
Me: 48 - Married, straight, male
Shiela: My wife.
Suzanne: My FWB
Adam: Shiela's LDR