The bottom line is - they know you exist. If you are a real threat to them then they will find out anyway - how hard is it to ask a mate to sign up on your behalf and forward the email or use a disposable account.

They aren't doing their job properly if they aren't watching you like a hawk. (and, by the same token, you of course you clearly are doing yours properly because you know who your competitors are and and paying attention - which is a good)

You need to measure everything you say in public as if it is lowering barriers to entry/ giving a competitive advantage to someone else. If you are in a really competitive space then its going to be like this from here on in.

However its good to remember - its the execution that counts and not the ideas.

Good luck