Quite. What would be the point?
Perhaps to show the total inner coherence between the two accounts, purported to be written by the same person?
After all, the Ascension in Luke's gospel is described as occurring a few days after the Crucifixion*, whereas the account in Acts relates that Jesus stayed around for forty days after the Resurrection. Now what could be more historically accurate and consistent than that?
Unless the supposed author had some other significance he wished to convey by his accounts of the Ascension? Jack Shelby Spong, the floor is yours....
*On "the first day of the week" - the day of the supposed "Resurrection".