>>noble
Not especially. There are some things that I really need on a given day (in which case I do use 2-day shipping), but with something like a new pair of shoes or some non-essential food item, it really changes nothing for me to wait, and yet the carbon footprint is substantially different.
Frankly, I don't even check my mailbox daily (it's 2 miles away). If it gets sent via USPS, it might sit there 2-3 days before I bother to pick it up.