Stupid company with absurd return policy

I bought a duvet inner which by the way wasn't my first choice,I was coerced by the sales person to take the all seasons one,when I got home I realised that the duvet is just too baggy and big and I wouldn't use it,I took it out and placed it back into its packaging,today I call the store to ask if I can return it for exchange and they're telling me about "hygiene" purposes even though I did state I have never used it,I then proceeded to ask about the situation with a blanket and am told its a different policy,how the hell is it different when a blanket doesn't have anything covering it but I can return it and exchange, its a stupid law and they will cange my inner whether they like it or not,am not going to beg them for I have paid money for it,it wws never my first choice but their sales person's