You don't have to "give" your main email address, if that makes you uncomfortable for some reason; simply create a new one, after all it's completely free.
I care about my time more than my email.
Ok so login with your email then
The implication might be that if they're not willing to give their email then they will definitely not give their time.
You can create a throwaway Gmail account ONCE and use it for all demos for the rest of your life.
It’ll take most 3 minutes to do that.
very throw-away then
Yeah, nobody wants to go through that. Let us use for free and see if it's worth it.