I love that people do this. Do you really thing someone is going to write a web scraper and NOT include obvious things like converting AT -> @ and DOT com -> .com?

Also, who even worries about spam any more? I haven't seen actual spam in my inbox in years.

Should we just go "AT AT AT" or something instead? Or perhaps adapt from Mandarin speakers, who literally call the @ sign "the little mouse" ;)

Spam remains an issue if for whatever reason you're still using rulesets/blacklists/greylisting and the like, instead of Bayesian filtering.