I don't see how that is illegal because the cards WILL eventually go to EU (dealing with VAT up front is less hassle for both parties in my opinion). Unless there is an agreement to ensure that cards will stay in the US, only then charging VAT for EU MIGHT be illegal. I don't work for ALLMINE; just my personal view on the whole VAT thing.
You don't see because you don't know.
https://ec.europa.eu/taxation_customs/business/vat/eu-vat-rules-topic/chargeable-event-chargeability_en#_Imported_goods"Importation of goods from outside the EU
Basic rule
The chargeable event occurs and
VAT becomes chargeable
when the following types of
goods enter the EU"
goods that are not for free circulation in the EU
Your argument reminds me of a couple complaining at pre-paid buffet restaurant (not sure if you guys have these in EU, but there's a few places that charge up front in my city). Their model is if people don't like it, they can take their business elsewhere. I'm assuming the owner had dine and dash customers prior, and wanted to play it safe. I'm not saying people try to evade VAT here, but you have to understand from the owner's perspective. Also, a dude above you comments on how they could charge VAT prior to shipping, and I think that's a good too. But at the end of the day, businesses operate in the best of their interest, not the customers'. If you disagree, just take your business elsewhere like the buffet example above, and that will show them. Maybe when they saw the sales drop, they would change their policy. Just my $0.02