Wow, according to Joe90_guy's lube report above, GroupIII base oil is 90 cents/quart. Treat rates with non-base-oil is what, like 20%. So 72 cents/quart for motor oil in just the base oil.
I have no idea what a 20% treat would cost per quart. Guessing those special chemicals (VM, esters, PPD, AW, FM, etc.) would add $1 per quart, then thats $1.72 per quart wholesale price for a GroupIII full synthetic motor oil, fully formulated.
Packaging would be say 20 cents/quart in volume. Rounds to $2. Shipping and profit per quart puts it at around $3.50/quart to Walmart's door. Add retail profit of $1/quart, and Walmart should be selling full synthetic at $4.50/quart (SuperTech).
I'm not far off, as Walmart.com actually sells 1-quart bottles at $4.97 instead of my $4.50 guess, all-groupIII synth SuperTech oil from Warren.