My goals are similar. I don't have a catch-all configured, but I have shop@example.com, and often use it with +aliases. Something like shop+epicgames@example.co

My goals are similar. I don't have a catch-all configured, but I have shop@example.com, and often use it with +aliases. Something like shop+epicgames@example.com. I don't have to set those up on my phone, and I generally found cashiers and other customer service to be understanding (they mostly do not ask twice, except for confirming that "plus" is indeed "+"). Once I was looked at like I didn't understand what an e-mail address was supposed to be, until I told them my custom domain name. That works fine for the majority of use-cases, but some refuse the "+" character, others (rarely) refuse my custom domain. Once, a shop refused to have its name. For the edge-cases, I generate a new e-mail address, and sometimes drop them an annoyed e-mail with a technical explanation of what's allowed and how to check for it. I think most client-side verification is here to avoid typos, but it shouldn't lock out the unexpected. Websites might have more success asking users to double-check unusual e-mail addresses or likely typos (like @gamil.com or smantha.lastname@... -- typo in first name), without outright rejecting them.