I've often thought that I should find more 5 quart cans (out picking) then 1 quarts because a 5 quart gets saved where a 1 quart is used and tossed. Unfortunately in my experience that isnt the case, but may be for others.

1 quart oil cans only have any value at all because they were in general thrown out immediately after being emptied, otherwise we'd have more survivors - a prevalent theme in this hobby