I don't know if you were trying to make a joke or not, but you are absolutely right! With space travel, both are needed to tell time. Things get even more complicated quickly. Albeit, things like 15 minute timezone offsets from UTC will become a terrestrial problem.
To you and everyone using things != .+@example.com: why? Example.(com|net|org) were specifically created for this purpose and for the purpose of tutorials. I work in client-facing support, and it's very easy to troubleshoot software that /other people/ write when the client says something along the lines of "It says 'connection to example.com:25 failed'" -- I instantly know what the problem is. If you're using things other than example.(com|net|org) for this, you're possibly making the job of a support tech you'll never meet harder.
If your excuse is "I didn't know about example.com!"...well, that's a lame non-excuse. Do the rest of the IT world a favor and fix your tutorials and software -- mail server administrators like me already have enough headaches from the gazillions of spam techniques in use today.
Ignorance is a legitimate excuse. I'm getting sick of people spreading this moronic misunderstanding that ignorance is not an excuse. Just recently the police in NYC failed to follow a judge's order out of ignorance. I wonder what excuse they used.
As for why people don't use example.com, if you're signing up for a site that annoyingly makes you put in a password it will check for non-real email addresses so example.com is out.
