Airmann is no doubt primarily interested in the technical calculations.
But as GG, JFP, and OG allude to, there are operational reasons for picking a MLW.
It's been mentioned here before that some operators "derate" their own weight limits so that they fall into a lower weight category for weight-based landing fees. As well as landing category, etc.
Airbus says the plane can take the landing forces at 62.5 tonnes. EZ decides they'll never need to land above 61 tonnes - so why not list that as their own limit, and pocket the savings?