I almost never have my yarn wound, I always do it myself by hand. It gives a lot more control on how the tension is and I make pretty kickass center-pull balls :D

I sometimes use a chair, but usually I just sit on the edge of the couch and spread my knees out and put the hank around them, (on in my recliner with my feet up if I'm feeling slouchy) it lets me control the tension on the hank while the yarn is unwinding too, and then I can move the ball around however I want while I wind it by hand.

As far as the scarf only taking one ball: Did they know you intended to knit it in garter stitch? I could see it very easily being a one-skein-scarf in stockinette, though still not an especially long one.