-ask for a new one and sell/gift one or keep both
-ask for a partial/full refund
-send the old one back and a smaller discount (for your troubles)
I would be more than satisfied with any one of these options. A partial refund is the most fair/reasonable/doable one for both sides IMO (unless you really do want a brand new pretty one, but you're gonna get it dirty anyway).
Weber One Touch Gold
2001 Weber Genesis that is no longer used since the OTG