Earlier quoted context omitted.
I know a guy who uses a service that creates a unique email account for every service he signs up for. That way, he tells me, if he ever gets any spam, he can delete the account and it doesn't affect any of his other email accounts.
With gmail, you don't need it - foo+bar@gmail.com will end up as foo@gmail.com and you can filter by To: header.
First because it leaks the underlying email (you can safely assume all spammers are well aware of this feature).
Second because if you start receiving spam, you can't stop it. All you can do is to try to deal with the firehose.
A much better solution is randomly generated aliases that you can delete.