I already have a cross bike (bought new last year) that works pretty well for gravel with a number of gravel races and lots of miles and elevation on it with no problem. A local guy is selling a gravel specific bike that I love the look of but is essentially the same geometry although a little shorter wheelbase and 650b tires.
Other than n+1, why should I buy a gravel bike? Wrong answers only. Bonus points for adressing the inevitable eye rolls from the SO about another bike in the garage.
Economic stimulus. One person’s spending is another person’s income. You gotta do your part to keep the world going 'round.