I can see no positive reason for this at all and some negative ones
The operating current is 60uA and 16uA on standby which it reverts to after 5mins in activity. I have sometimes seen these cells paralleled up to meet a peak current requirement but there is nothing like that sort of current being drawn by a couple of chips and a LCD display
Each cell is rated at 230mAh which should give around 3800 hours normal operation and 14000 in standby so well over a year with mixed duty cycle.
SO why on earth are there two cells fitted??
PS it is a digital readout scale - a bit like the cheapo verniers but a lot longer.