Yeah, some friend just concluded yesterday that this might be giving (2nd hand) record stores worthy function again. Suddenly getting 2 euro for CD or 5 euro for LP ain't that bad. It might be the same you would get after fees and all the work when selling something at discogs.
I know there are different kinds of customers and markets out there, but as record store owner, I face the devastated sellers every month. Meaning guys, who have good stuff, and have browsed a bit discogs, and think they have amazing collection worth a lot of money. Then I can mention that almost none of this stuff is worth what discogs says. Not here.
Out of the realistic money one gets for them, you get like half. Or 1/3. So album that someone would buy for 10 euro, you get 4 euro. Rest goes to taxes and couple euro "profit" for shop. So... when thinking your "discogs average" is suddenly not really accurate in real world, where idea is also to get rid of things and not wait for that 1 guy in world that pays maximum price, real world average at least over here is significantly lower. Selling to 2nd hand stores, you lose opportunity to make bigger income, but win TIME. Freeing storage space, not having to deal years and years with bozos.
One can think usual discogs situation where 50 people "want it", there are 5 copies available for X amount of money that isn't even very high.. but nobody buys it. So whatever transaction may have happened before, now it appears to be actual value starts to be visible and even if someone paid 30 euro once, it may be worth 10 or less to everybody else... I my store I see it all the time. People who would want "rare record", but in the end, don't buy it. Most of rare records take ages to sell, despite would be priced significantly lower than online.
I had discussion some years ago with guy who asked don't I buy rare collectible stuff into my store. I explained situation above. Sure it looks neat when you got rarities on shelves, but most customers prefer to buy 10 new CD's or tapes, as opposed to one 90's original Japanese noise LP. Same for metal. And I know this for my own habits too. While rare cult records can be great, there is so much great new stuff that is right now happening. I understand the hunt for old rare, but it is quite similar task when hunting for new good. What a delight it was to get couple NEW Mlehst CD's, and discover they are actually GOOD!