De-spinning necessary?

Would it be absolutely necessary to de-spin an asteroid before it's
brought back? If the spinning was not too irregular, you could attach a
tether at the axis point and tow it back to the processing plant, spin
and all.

Eventually it may need to be despinned for processing, but this may not
be necessary right at the outset. If it was de-spinned back at the
processing plant, then AsterAnt won't need that extra bit of fuel.

--Chris