Heckel -
Well not really unless you want to be EXTREMELY strict. First off Alberti basses could be orchestrated in many ways - in this case we can hear the top repeating B as a pedal point held by woodwinds while the E-G third could be orchestrated as tremelo in the string say. In any case, the B would act as a pedal while the E-G would be the more fluid voice. And to simplify it to a vocal texture , it would be simply a E minor chord sung every quarter or half note. So looking at the top note of the chord the B, we have the following intervallic relationships with the figure in the bass - maj 10th- P8-P5.
It is always important to consider the tempo - at the speed this piece goes you would not notice it. Plus if Mozart tried to avoid it with same pitch material, the only option would be to have the B transposed DOWN an octave - which would actually create GREAT discontinuity in the music. As it stands I'd say the parallelism you spot contributes to make the figures sound more galloping than before and in keeping with the feel of this piece.