winjim
Straddle the line, discord and rhyme
Wet lube you can buy by the gallon, but dry lube is too volatile to sell in bulk and certainly wouldn't keep for the 63 years claimed for your 5 litres of chainsaw oil.No this is the problem with comparing apples with pears, but I wager you could buy a drum of cycle specific oil if you really wanted and save a substantial amount.
Whilst I agree that we all need to make responsible purchasing decisions, seven quid for a 120ml bottle of lube (it's not just oil) every two years or so is simply not going to make a significant difference either to my financial situation, or to my environmental impact.