They made that problem with the batteries for themselves. I have owned a couple of different mac laptops, and the ones from 2011 and earlier used to have a built in bracket on the battery that stabilised it and made it trivial to fasten and unfasten with screws.

The brackets did not take up all that much space, but apparently it was worth it to them to save a few minutes in manufacturing and a few seconds in assembly and just use adhesives directly against the unibody for fastening and stabilising.