They don’t accept addy.io domains and then I checked the privacy policy, which seems quite iffy to me:

Vinted transfers or shares personal data with service providers only insofar as necessary and allowed in accordance with applicable laws. Service providers to which your personal data are transferred or shared with for specific purposes are described under 2 above. In addition, we appoint the following service providers that, as a result, receive personal data as recipients of data.

[…] The following service providers are established outside the European Economic Area, which may result in your data being transferred outside the European Economic Area. In these cases the personal data is protected by the service providers entering into the EU standard contractual clauses for the transfer of data as approved by the European Commission:

Amazon Web Services, Inc. (USA); Google LLC (USA); Apple Inc. (USA); Microsoft Corporation (USA); Slack Technologies, Inc. (USA); BlackLine Systems, Inc. (USA); Chronicle, LLC (USA); True Partners Consulting, LLC (USA); Arcaris, Inc. (USA); Havas Edge, Inc. (USA); Cloudflare, Inc. (USA).

We transfer personal data to attorneys, attorney assistants, notaries, bailiffs, auditors, accountants, bookkeepers, debt collectors, consultants, translation agencies, IT service providers, insurance companies, archiving services that provide services to Vinted.

I really don’t want to give them my proper mail address. GDPR or not (and they also were fined 2.5 million for violating the GDPR).