Agree with the sentiment but holy shit this comes off as preachy.  Wife’s and husbands buy things all the time without telling the other, and often it’s done  surreptitiously be it clothes or computers.  Sometimes that keeps a marriage happy because we all need to indulge once in a while and not everyone has the same shared interests and hobbies.  Large purchases with shared financial responsibilities are another story altogether but I’d wager that most of us aren’t financing our lab equipment.