Paying a lawyer to petition a judge for a subpoena (which the judge may or may not grant) is probably much more expensive than whatever Flock charges.
Paying that fee would absolutely be worth it in a costly divorce if it prevented someone from paying out.
I'm assuming flock have some sort of legal protection that gets them out of that for regular plebs. Otherwise people would hate them even more knowing they were used for people's personal matters.
The Government has full time lawyers on salary, they generally don't pay by the hour for things like that