We are no mind-readers, so we can't tell you why there is no way to do it at this point.
But the reason for the "standard" markdown not working is this: Table HTML is not permitted:
We do not (and will not) allow
<table> tags. Sorry. This is intentional and by design. If you need a quick and dirty "table", use
<pre> and ASCII layout.
And, as gertvdijk points out, this discussion has been had, and the answer is still the same:
It isn't implemented. That's why it doesn't work.
Except for yet again asking for it to be implemented and using workarounds, there really is nothing else one can do about this.