I couldn't imagine why not. You just to to a ticket machine and buy it, no need for a passport or anything. Enjoy - Sylt is waiting for you, and you'll be there along with a million like-minded people!
These are almost certainly subsidized tickets, financed with taxpayer money, it is common to restrict the sales to those who pay taxes in the covered area. And I don't see how it could be illegal, it is like forcing Germany to provide health care for the French and vice versa.
Maybe in some dream world. Hospital visits are usually covered, but going to a GP often involves paying in cash and only getting reimbursed later at home.
AFAIK the legal way to limit subsidized tickets is that the specific "membership" required to get the subsidized fare is available to all EU citizens - for example in Warsaw we can get lower fare based holographic stamp available from the city on the basis of paying taxes in the city - i.e. it doesn't matter what passport you hold, it matters that your tax residency is in Warsaw.
And healthcare operates by your local health system reimbursing the system in country you were visiting - you need to have European Health Insurance Card on you, from your healthcare provider, which helps route the payments appropriately.
It is still a good question, because there are often special conditions to these kinds of offer.
For example, in Paris, some "all zones" tickets are only available to residents (pass Navigo). The Japanese "Japan Rail Pass" is only available to tourists, and the "Interrail" pass is complicated: you have to reside in Europe but you can only use it in your own country for a single round trip.
The tickets aren't personalized (some regular monthly passes for public transport are/were though), so you should be fine. Since they aren't personalized and there is no way to check who the owner actually is, I would even expect them to be transferable.
Edit: looks like I was wrong -> see replies. You can also search for "9-Euro-Ticket übertragbar" (übertragbar = transferable) yourself to get a number of different German sources for that.
Normally DB day tickets, even bought at the ticket machine, are not transferable. You have to write your name on the back - in theory, before the first time you encounter a ticket controller - and be prepared to produce ID matching the name.
>People who use local/regional transport will be able to buy it anywhere in Germany via channels such as bahn.de and DB Navigator. It will also be available from DB Reisezentrum (travel centre) staff and ticket machines at stations.
Ticket machines can be used without need to identify.
However, contrary to what is said multiple times in this thread, it is NOT transferable. You have to put your name on it and have some form of ID with you.
Pretty sure it's just Germany being pig-headed about it for some reason. Everywhere else in Europe is perfectly happy to accept a credit card. I do 99.999% of all my spending on a credit card, like most millennial people or younger, and the only people in the developed world who this is a problem for is the Germans.
Why not at least google some statistics before you lose yourself in some pig-headed chauvinistic rant about what in the most charitable interpretation amounts to nothing at all.
To be fair, I find it absolutely absurd that credit card companies siphon off 3% or so of all retail purchases, and then distribute a part of it back to their "most valuable customers" in the form of miles and cash backs and similar time-consuming nonsense. It is redistribution from the poor, those using cash and those not being able to pay off credit cards in full, to the rich.
The EU has imposed caps on these interchange fees [1], which is one reason Europeans are not inundated by junk mail offering credit cards, and may be a reason that credit cards are not ubiquitous. Having said that, I find that I can pay electronically in most places, including Deutsche Bahn ticket machines (or just buy them in the app).
Not hate, just not a system used very much here. Most people with a credit card have one for online purchases (I do), but those are a minority. Even that is no longer really needed with big stores like Steam and Amazon (.de and .nl) accepting the local IDEAL standard for banking transfers.
Paying with a credit card in shops? That's just not done excepting American tourists, same as in a number of European countries. It's contactless debit cards mostly. Building a credit rating by using a credit card is not part of the system.
EMV2-compatible debit/credit cards work pretty widely. The real issue is that some countries have locally-popular cards that don't work in that scheme (Dutch old Maestro variant, some german cards, etc.) or have very annoying compatibility issues (my old "Visa Electron", once very popular in Poland and which tripped UK card systems like crazy) and availability of card payments differs across EU - capping card fees and speeding up transactions thanks to EMV helped there a lot, but I remember hearing stories of Italian shops in touristy areas getting card readers... because of Polish visitors, who were accustomed to wide availability of cards (last local bastion of cash only was farmer's market nearby - now every more established stand has one)
I had no problem paying with a credit card on Bahn.de ticket machines (White and red). The yellow BVG ones gave me problems in the past accepting an Argentine card, but it’s likely it’d take it now that it has a chip.
Another hypothetical alternative which wouldn't violate EU law (not that they have any reason of using it) would be to make the ticket only valid to people who legally reside in Germany, regardless of their nationality.
