People who grinded Hand of A'dal, Black/plagued protodrakes, Black Qiraji Battle Tank, Immortal/Undying, Champion/Conquiror of Ulduar - they'll have it forever. In five, maybe even 10 years they will login into game and people will say "Hey, your char is so cool".
And what is most valuable - is memories. Memories about how you and 24 of your friends defeated epic bosses after hours and days of the extraordinary hard gaming.
I can open my achievements and say "hey, I remember this kill, I was in guild X on server Y and this boss was the most badass fight I ever experienced. Hey, I got my weapon from him, here it is in the bank, still enchanted with oldschool Mangoose enchant".
In d3... you spend thousands of hours clearing the same route over and over and over and over and over again.
Grinding? You never use items that you grind. Everything that you have you bought on AH. And in just 6-8 month you'll sell all the items you have to vendor because new expansion will bring ilvl73 items and your items will become useless.
"- How was your day, diablo3 farmer? - I killed 300 elites today, it's much better than yesterday, when I killed just 250 elites. Memories? I remember the alternative route that I used to run until someone showed me this one."
Obviously you are quite new to d3 if you don't yet understand how unrewarding and useless is grind in d3.
Sooner or later you'll realize that playing AH is 10+ times more rewarding than farming. And after that you'll realize that working in macdonalds and using real life money to buy whatever you want in d3 is even more rewarding than playing ah.
But it's a long way to understanding. Come back in few month and tell us about how rewarding was your daily grind today.