Craft brewers already list ABV, IBU and SRM and well as calories
eg.
http://brooklynbrewery.com/brooklyn-beers/perennial-brews/brooklyn-brown-ale
“Style: American Brown Ale
Malts: British 2-row, Belgian Aromatic, American Roasted Malts
Hops: Willamette, Fuggle, Cascade
Alcohol by Volume: 5.6%
IBUs: 30
Original Gravity: 15.5° Plato
Calories: 190”
From what I understand, it’s not that difficult to figure out calorie counts - just plug the ingredients into a program and the count comes out. It’s not like it has to be measured as actual calorie output when burned.