SNCB has a discount club called “Train+”. Membership gives discounted prices on off-peak travel. Found this in the terms and conditions:

1. Reimbursement of Train+

• Refund is possible if you have become Train+ via sncb.be or in the SNCB app, and provided you have not yet used Train+. The refund application must be submitted in writing to the Customer Service within 14 calendar days of purchase.
• In any other case, Train+ is not refundable.

The app is exclusively limited to people with smartphones and a will to lick the boots of either Google or Apple. The website is also exclusive due to shitty anti-bot challenges and deceptive gatekeeping (e.g. Tor users perpetually get a false error msg: “website under maintenance”).

Is it legal?

EU Regulation 2021⧸782 has this:

“In light of the development of online platforms selling passenger transport tickets, Member States should pay special attention to ensuring that no discrimination occurs during the process of accessing online interfaces or purchasing tickets.”

That is written in a recital, not an enactment. So IIUC it has no force. It’s merely the sentiment of the lawmakers.

SNCB has converted into a privatised profit-driven corporation that no longer receives government subsidies (supposedly). There is apparently less pressure on them to be fair and free from various forms of discrimination, so they can take the piss. It’s all about the bottom line.