Whoa! Let's just begin by saying that the historical truth of the bible has not been demonstrated. Indeed, given the historical inaccuracies known to exist in the bible, there is actually a great deal of reason to doubt everything in it. Including this entire story.
But let us assume that the story is true for a moment. I've heard this claim many times before. Women were such a low status on the social scale, why continue telling the story this way? More likely, if it didn't serve their purpose in some way, the story would have been told another way. As I've mentioned before, classical writers played a little hard and loose with the facts. So, if it was to their early Christians' advantage to have women find the tomb, what advantage was it? Or was it simply that women were so low on the social scale that only women were allowed near the tomb? And to say anything else would have exposed the story for a fraud?
There are any number of explanations for these particular facts. And given the dearth of information we have from that period and the dearth of non-scriptual evidence for the life or death of Jesus, it's highly unlikely we will ever know what the truth was, or the motivations for the story. All we have, at best, is speculation. And speculation proves nothing.