Lots of supposition, there.
First, there's a move to have those embryos adopted by couples who can't make their own embryos. There has also been a move in the last few years to make fewer embryos, so that there are fewer to store. It is also possible now to freeze harvested oocytes, rather than make more embryos than are to be implanted.
Second, we are all going to die, but that does not negate our right not to be killed by someone else. Why don't we turn all death row prisons into organ farms?
Good all. However, for the foreseeable future, far more embryos will be WASTED TOTALLY, than are implanted. There is no logical reason not to use them.
Also, you and I disagree on whether or not an unimplanted embryo is in fact a human yet. Thus, using the "murder" term at this point would be like saying "every sperm is sacred...". Or at least singing it.