Money comes with strings, such as when forming an ongoing relationship with a company you expect them to not merge with other companies you are actively prosecuting. I suspect the deal is going so fast to avoid some sort of veto being prepared. Once SpaceX and xAI are officially the same, you lose the ability to inflict meaningful penalties on xAI without penalizing yourself as an active business partner with SpaceX.

Was it a grant or a purchase? If I buy a pizza from the pizza shop, it costs them $10 to make, I pay $11, the $1 is profit and the owner can do what he wants with it. But if I get a grant from NLnet I have to spend it on what the grant proposal says. Though a lot of NLnet grants are for living costs while doing a project, so I can do what I like for that time if the project gets done.