"Speciality coffee doesn’t offer anything to the consumer who wants to drink great espresso at home, but doesn’t want a new hobby." This is an amazing take away, and I think many coffee roasters, gin distillers and beer Brewers ought remember it.
I take the OA's point, however most of us (I assume) will be using a cafetiere or a paper filter based coffee maker at home rather than doing the full artisan roast and grind. In my case, I'm using pre-ground coffee in foil bags from the local supermarket at around £3 to £4 per 227g standard pack. I make myself a large diluted coffee each morning using a 3-cup mokapot. The 5 minute prep time isn't onerous and the eco…
Coffee starts losing aroma quickly after grinding. If you buy your coffee in a speciality-store and they grind it for you there, you can definitely smell the freshness of the coffee as you take it home.
It's fantastic, but after not too long that fresh aroma dissipates, and wont return. Imagine if all that aroma could have gone right into your cup.
With a proper grinder at home, you always grind the coffee you need, when you need it. And you will have all that aroma in every single cup.
Besides the digital weight, I think a proper coffee-grinder is one of the most important things a proper coffee-geek can have.
You probably don't need nor want an Italian art-deco piece of 60s futuristic polished steel priced at $1000 and upwards. But investing at least $100 into a entry-level grinder will get you coffee miles ahead that pre-ground stuff. I assure you it's a noticeable return on investment.
So yeah. Grinder is definitely recommended.