protic vs aprotic

According to many books, protic solvents favor E1 and Sn2 reactions.

Why is ethanol frequently used in E2 reactions???!!!

Here is an example:

[(CH3)3C-Br + CH3CH2-Na+ ](in ethanol) -> (CH3)2C=CH2 (97%) E2 rxn*

*McMurry page 409

On page 385, McMurry says the following for E2 and Sn2 reactions: "Protic
solvents form hydrogen bonds to the nucleophile, increasing deltaG, and
decreasing the reaction rate. Polar aprotic solvents surround the
accompanying cation but not the nucleophilic anion, thereby raising the
energy of the nucleophile, decreasing delta G and increasing the reaction
rate"

McMurry and other authors often use ethanol which is polar & aprotic for Sn2
and E2 reactions (esp. for E2). Why don't they use DMSO and HMPA more
frequently???!!!

In the case of tertiary nuceophilic centers, doesn't the use of a solvent
(protic or aprotic) make a rxn E2 or E1??



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