I believe many of the rentals down there (from what I have been told) are AL80s. So it makes perfect sense to not want wings bigger than 50#. Gets hard to vent them on 80s which makes for a mess in training...
There are no steel doubles for rent (at least there have never been any staged at the community fill station I use). There are 40 or 50 sets of AL80 doubles moving through there on a daily basis though.