Maybe they are also on the process or discussion on how to maximize their profits and make the fight bigger than mega-fight as an undisputed fight is really rare to happen in the boxing industry, also, I happen to read somewhere that Spence's camp is asking for Crawford's camp to help Spence sell and market the fight as he couldn't carry all the load even if he is the king of PPV. Don't know if it's really true but both of them should really try to sell the fight even if they know that their fight is much anticipated.
They share the obligation but I'm curious since both fighters are top calibers and their names already have market value.
I don't see any needs of selling as in one formal announcement of this possible fight fans will be there to support, especially the gambling industry
Exerting more effort into the marketing will help them sell more, more PPV and gate entrance means more money, and probably more sponsorship as well. This is an anticipated fight and it could only happen once, so they have to take this opportunity to make more money.