It's brilliant getting a great new record and slamming it on that day or weekend. Everyone loves that. And on that point also, I actually think the physical action of fetching a record from my bag and throwing it on is what I love most about vinyl, it can't be underestimated!
I guess my reading of a lot of the people that only play new music is that they're just involved in a back scratching exercise with friends, labels and promotions companies... and are doing it to ultimately just to feel 'upfront' and continue getting free music - a lot of these people wouldn't even dream of going to a record shop and some rarely buy any music at all. We all like free music from time to time, and when you get something amazing it's great... but 'digging' and searching is what seperates you from the next person, and what's more fulfilling than finding a great record or something you were after, in a record shop?
Nothing.