[sleepychu]

In that regard though, it's not different to existing throwaway email services. I'd use this sort of thing for registering for annoying things like "free" wifi.

[faissaloo]

Most free wifi hotspots don't verify your email fyi

[basil-rash]

To some extent, they can't. (How do you verify the email without being on the wifi?)

[dzek69]

some may allow popoular e-mail services (and imap/pop3 ports) traffic, while blocking the others

[kees99]

other captive portals let user in, ostensibly to open inbox and click the link, then kick off the net if that didn't happen within 5 minutes.