I see your point, but for some, it's easier thought than "said" to decline what has been offered. Even if free. He/She may have just wanted to see the variations of what would be offered with his/her request. Many times when people make a request, they may have a specific look in mind that they are holding out for. I don't think he/she meant any ill will, but I see why it upsets you.
As far as me being a designer that has happened once or twice... When I make a pattern it can take anywhere from one hour to 3-4 hours. I am somewhat picky in deciding which one's I'll tackle to begin with. I've had personal emails sent to me where someone requested a pattern that I have not made yet and was told "If I have to pay for it then nevermind". I wish I didn't need the income so darn much lol. I've had a few folks post finished work that wasn't my pattern after I had offered it, but...ya win some and ya lose some. As far as alterations to my patterns, I believe that's 100% acceptable. Nobody will want to cut something they don't like.
I, for one, (among many) appreciate the time and efforts so many people on this forum give to each other. (I also appreciate Steve and Russ for all they do to keep it running smoothly).