Things that make you go, "Hmmmmm...."

I’m wary of used players in general because the transport is largely a mechanical device and can wear out or get sloppy. That’s been the weak link that led to the demise of both of my retired players - Adcom and Ah!. I briefly had a Rotel, but returned it for (you guessed it) transport issues. Using an Oppo now, and yes, I often stream ripped versions, but it’s always nice to have a hard copy. I like to read paper books, too.
I’m not sure how playing direct from CD can sound better than streaming the same data, given comparable DACs, but obviously there is strong anecdotal evidence that it is possible. Don’t overlook the attraction of ceremony in playing music as well. I’ve never been able to get past the inherent noise of vinyl, but the inspection and cleaning before playing is enticing. While audio is primarily driven by what we hear, it is often enhanced by the other senses and rituals. I’m going to be sad when my CDs succumb to mold or material fatigue. Eventually, I’ll need to pony up for a robust transport that can go the distance. I hope there’s something nice available when I get around to it. 

Lots of over-the-top responses here, and tortured analogies.

I'm using an Electrocompaniet  EMC-1UP that is ~17 years old, and it still sounds excellent. I paid around $2300 for it used (it had also been modified) around 2006, and I see some advertised now for ~$1200 to 1500 (mostly in Europe). That's a far cry from going "to zero".

Am I missing out on meaningfully better sound through "higher resolution" streaming files? I rather doubt it. Not suggesting that no difference can be heard, at least on some systems, but I have never sought perfection in this hobby, instead building very good, synergistic systems that suit whatever space I happen to be using.

It is, of course, true that CD players all have weaknesses, and that parts will eventually fail. So yes, if one hopes to keep a good player working for a very long period of time, spare parts and those capable of doing repairs can be issues. But I find the implied assumption that streaming services will necessarily survive, or that the costs will remain reasonable, to be potentially naïve.

Some of the objections are just plain silly. Does anyone really need access to "millions" of songs? Is it really such a chore to leave one's chair every 30-40 minutes and replace a CD?

As for this:

"There’s no benefit to playing CDs on a CD player anymore."

it's simply not true. Owning a hard copy of digital media certainly can be an advantage. Although the analogy isn't fully taut, I own many film DVDs, and most have paid for themselves several times over already. Again, I appreciate that it's a different market, but many of the more esoteric films are not available on streaming services, and the DVDs have actually gone up in value over the years. Never forget that, even in the case of music, if you don't own it, you are largely at the mercy of those who do, both in terms of access and cost.

CD Unit to buy: Marantz SA-8001.

@millercarbon Thank you for asking a good reasonable question. It never ceases to amaze me how people have to preach their biases instead of actually addressing the question asked.

I have several thousand CDs including HDCDs and SACDs. I like the experience of playing them as discs. I realize that makes me a troglodyte but so be it.

I currently own a PS Audio PerfectWave Mk II transport and DAC that I got for about 40% of retail after the DirectStream came out. It's worth 80% of what I paid for it. I also have a Krell CD 250/2 player that's worth 90+% of what I paid for it. My third player is a Marantz SA 8005 that I got used. I see them selling for around 90% of what I paid for mine several years ago.

Here are some other recommendations:

Vintage Krell or vintage Mark Levinson: If you buy a good condition model with original packaging for a fair price it will hold its value. Examples are ML 360s DAC with a 37 transport, and Krell KPS 20i. These units decode HDCDs (I have a couple hundred) which is not available in new players. You can still get transports for both players but it would be wise to acquire an extra when you get the player.

Emotiva ERC-3: I bought one new and sold it for slightly more than I paid for it. This was a classic piece of gear that decodes HDCDs (Emotiva's new players don't do that). A pristine player with original packaging should hold near 100% of its value indefinitely.

Any vintage player that received a Class A rating in Stereophile that you can buy on the used market - especially if the player broke new ground in some way and if it is from a major manufacturer still in business. I own several pieces of high end vintage gear from the mid 90's through the mid 2000's and the depreciation curve seems to have flattened out for all of my pieces. Besides holding its value this kind of gear has a special pride of ownership because it was so well made and because it was absolutely state of the art when it was new. I love this stuff and playing a file from my tablet just doesn't give me same satisfaction.