Old oil contains the contaminants that the detergents and additives were designed to remove in daily use, not to mention if any moisture were to build up in the old oil
Short motor running is a no-no in winter, you havet to get oil up to 170+ or so for it to start working properly, so if you start it and let it idle 5 minutes in 30 degree weather you are not doing any good, plus you'll let moisture build up in the exhaust - rust
Fresh oil at least won't have any old schmutz suspended in it.
If you are really anal -
The Scavenger would be good to have to use before storage.
I got one just to see what it would do, and it works pretty well, JMO the hose that comes with it is too short so I've got to get a longer piece of hose but you won't believe the amount of black oil that is pumped out before the clean oil comes through.
For storage it would be good, and I use it about every other oil change, heck I don't have anything else I can do to the bike so I need something to screw with.....
Yeah it's pricey but it is a nice piece of USA made stuff and it works.
This was not a paid for promotional advertisement and I was not solicited by or promoted by ACORN in any way....
We plan to meet next week to talk about planning a strategy session to discuss the next step towards forming a consensus to start the development of the rough draft for the implementation of our intention to develop a plan. 
, dang get warmer clothes, keep riding till the ice sets up then you can ruin my day
