Why would you want to waste perfectly good fuel? Sure, you will get slightly better fuel economy after you remove the alcohol, but at the cost of ~10% of the original volume. Slightly better fuel economy, but lower range.
After all, the energy content difference between E10 and Regular(No Ethanol) is only about 3.2%.
I say just use it. Regular E10 with the ethanol removed will have a lower octane rating, but buying premium to make up for this only ends up costing you more. One of the main purposes of adding ethanol to gas is to reduce overall gasoline consumption by stretching current supplies by "improving" the octane rating of poorer gasoline.
While it is an interesting concept to remove the alcohol for slightly better fuel economy ratings, it isn't cost effective in the long run.