Who positions their speakers straight ahead (zero tow in) and why.

Think of speakers as backwards microphones, which they are, you would always want to point the microphones exactly at the thing you want to record because the mic is designed to be most accurate on axis. Off axis coloration in microphones is very important and the thing that separates good and poor sounding mics same with speakers they sound most accurate exactly on axis. 
So
Point your speakers at your ears the left speaker at your left ear and the right speaker at your right ear. The off axis coloration of speakers is best dealt with by room acoustics. Thinking of speakers as reverse microphones makes many things in acoustics obvious. 

I ended up with my Magnepan LRS+ pointed straight ahead after trying many other positions..

And nobody commented on Wilsons.  They are usually positioned with generous toe in but... often spaced apart more and so closer to the sidewalls.  Or they can be closer together with less toe in.  Never my choice.  And, as someone has said, about four feet out from the wall behind to give sensational depth. 

Mine are actually toed up since otherwise tweeters are too low

My speakers are big ADS 910's, in the cradle stand for up/down adjustments.

My small room is 12'2" x 15'9" with 9' ceiling.

I have looked at every speaker position website and find Cardas most helpful.

If you are familiar with the ADS 910, both speakers tweeters are on the right side of the cabinet with the mid beneath and to the left, and two bass also staggered toward the left.

None of them are in the center midline or directly beneath one another.

Because they are asymmetrical, an accurate toe-in for each, or straight ahead position, or ideal distance from side wall in such a small room has been impossible to calculate.

My solution has been to stow the masking tape, slide rule, level, weighted strings and tape measures and near field listen with my chair about 3-1/2' in front.  The speakers are toed in but unequally because of their size in a too narrow room.

Looks very dumb but the sound is satisfactory.

For me toe in or straight ahead is everything...and nothing.