The short answer to this question is No.
Would you let one user stop a different user from receiving email? Of course not because they don't have the authority to opt out (or in) for someone else. If a person opts out of receiving email then nobody else has the authority to opt them back in.
Legally anyone is free to send non-threatening emails to any address they want but there are more effective ways to communicate with customers. Even when people opt in to receive emails from you most of them will never be read.
I think there is another question being asked here so I wanted to address that as well.
How do we engage our customers and keep them coming back during the off season?
1. Relationships are a two way street
No matter how much you want to have a relationship with someone it won't succeed unless the other person also wants to have a relationship with you. If someone opts out of receiving emails from you then sending them one for any reason will do more harm than good.
I actually opted in to receive an email once a month from my Nest thermostat because this let me see how much energy I was saving compared to other people in my area. This was an email I would read because it had information specific to me. It added personal value. At one point my Nest device wasn't able to connect to the internet anymore and went offline. I knew of the situation but didn't get around to fixing it for 3 months. Nest didn't send me any email during this time. They must have concluded that sending an email without any information wouldn't be interesting to me. They concluded right and my personal opinion of Nest was greatly improved. I was glad to get the technical issue fixed on my side and start back up that relationship!
2. If a community adds value then it will get used
Without knowing the personal nature of your business I can say that adding personal value to an individual is really the only way to get them to seek you out. Why do so many people return to this forum almost daily? Why do we help others and answer their questions? Because we learn things ourselves and become better over time.
3. Social Media - A fun contest can build up a community
Even if you have something that provides value you need a way to get the word out. Do a silly contest like
Tweet a picture of your best dance move to us for a chance to win an iPad Air Reply to these tweets with personal messages of encouragement. Just know that once the contest is over the people won't stick around unless the community really does add personal value to them.
4. Gamification - Reputation is the new currency
One final tip would be to reward users that participate in the community. Stack Exchange does this well.