This class clown (me) finds this amusing , thanks for that. Reading the rants and some shorts getting wound up over some alcohol 
I'll start with 'what to do to get up to 300k miles, the business side.
This is from experience as a station owner in the 80s, a racer that had to go through fuel tech and a hobby farmer using vintage and antique tractors.
1- Buy your fuel from the most busy stations to get the freshest.
2 -If a tanker is on site and is dumping fuel come back the next day or get it at you next favorite station as the dump stirs up the water and sediment at the bottom of the tanks.
3- Ask If the pump has a 5micron filter, water won't pass through that tight of a filter. AKA as a 'water separator' and those need to be drained at intervals. If the fuel is coming out slower than you remember it's probably loaded up.
4- Buy your fuel in the early morning because the fuel is more dense and you actually get a very little more for your money and the crap is more settled in the underground tank.
Anhydrous ethanol as an additive has a greater up side than expected. It is hygroscopic and that way it combines with 'water' and pulls it through the system with out little to any harm to the fuel system. Think about it... when was the last time you had a car die from sucking up a gulp of water or for the northern guys when was the last time you had a gas line freeze up. Remember adding 'DryGas' or 'Heet' to prevent that? I do. That stuff is anhydrous methanol or azeotropic iso-propyl alcohol to 'absorb' water/condensation.
1- It replaces MTBE (methyl t-butyl ether) and that 'stuff' is bad/worse for you/us.
2- The 'white power' left from evaporation is not new and exclusive to 'gasohol'. I occurs/occurred with MTBE also. It can be much worse in carbs that are vented to the atmosphere (as Sam said) and also there is an etching reaction in zinc chromate and aluminum carbs. With a sealed system as in a EFI car/truck it is 'not a big deal'
3 - Both Anhydrous ethanol and MTBE are added as 'oxygenates', Other specific 'chemicals' are also add to make up what we know as gasoline containing an additive package that varies by brand to enhance shelf life, set Specific Gravity, Reid Vapor Pressure, evaporation rate and detergents added to reduce fuel system deposits.to help keep fuel systems clean,
Back to "your" car.
It's not how many miles you put one it in a given period, it is how you put those miles on. What?
Short trips to .. um.. Waffle House where the Motor, Trans and Diff do not get up to operating temperate to 'burn-off' the condensate in those oil filled housings can/will shorten the life of those subsystems. Of course the time/distance to achieve operating temp will vary based on ambient temperature.
the point is.
Adding a fuel treatment will have some but minimal effect on the total life of your fuel injected car. (with low/no maintenance crank windows 
)
Use the best fluids, grease and filters you can buy and change the regularly. No power shifting, brake stands, hole shots or J burns will help a lot ...LOL
Under carrage rust is another enemy to meeting you goal. When it is on the lift next time look carfully at mounting points like control arms, sway bars, trailing arms, body mounts and sheet metal belly pan/floors. An additive I would recommend is an upper cylinder lubricant add to your fuel. to spare the rings, walls and valve seats and guides.
Other things:
The gas pump states the octane rating and not to exceed percentage of Ethanol. 10% is the normal max. Ethanol can not be rated using RON / Mon methods so a calculation is used BoV IIRC so its final octane rating is AKI (anti knock index) is in spec. for an octane rating.
Locally:
100LL is $4.15
The UL non-eth 93 here is $4.01
The UL non-eth 90 is $3.49
The UL 10% eth 87 is $1.95
How "I" do it having a variety of 2 stroke carb, 4 stroke carb and EFI and diesel engines
I buy the sweet smelling heavy metal LL100 with 2.12 grams of Tetraethyllead. Price per gallon is $4.15 and mix it 50/50 (or less) with $1.95 unleaded 87.
At a cost of $3.05 9or less) per/gal I use it in my 2 stroke oil mix and 4 stroke non cat engines... and am happy.
I also always add a dash of Lucus upper cyl fuel treatment and Techron (Detergent) occasionally.
In my Cummins Diesel I add 8 oz. of 2 stroke oil to a 35 gallon fill up since they took all the Sulfur out. That is about a 500:1 mix. If my water separator shows more water than I'm comfortable with I add about 3 oz. of 99% Isopropyl when it gets down to just below 1/4 tank. A top Diesel mechanic said "just add a quart of trans fluid to your 35 gal tank. It turn to fuel read and that might new me to cause some Serious explaining if I ever got a highway fuel check. If you get caught with 'red' off-road fuel on the 'highway' it's a $12,000 fine and they take the truck. Thus.. the green 2 stroke oil instead.
I run off-road (red) diesel in my New Holland tractor with a 2oz. to 5 gal.
All this Mad Science keeps me thinking and entertained... LOL 
One more detail to is maintain a Stoichiometric Air/Fuel Ratio in a carburetor will require re-jetting at or above 10% eth.
In closed loop EFI and Electronic carb cars the oxygen sensor(s) will tell the computer to adjust the fuel mixture accordingly in real time.
That should cover it, if I think of anything else I will add it. 
the Koch brothers.
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