Not my understanding of how this works.

Not my understanding either if this is the case how come companies are in business selling data to other companies I am sure I did not give permission to any company who got hold of my details and are for ever calling me about PPI

Simple. Ring the ticket office and ask them why they have not specifically targeted last season's Season Ticket Holders regarding renewal as well as other regulars and why they haven't been sympathetic to the needs of concession ticket holders like they have in the case of sixtysomething. Barnet fans previously. (Precedent set?)
And then perhaps suggest it would make sense to contact these people separately from just a generic email, mailshot.
If I get time at work today, I'll do it myself.

I'll let you decide, obviously this is my interpretation that buying tickets for the Stoop from Harlequins RU does not allow the Hive to automatically use it for marketing purposes to sell tickets for the Hive. As others and I have said, the season ticket information held by Broncos admin staff should've been passed on and if it has then for the Hive not to contact these people makes no sense.

Organisations will generally need an individual’s consent before
they can send marketing texts, emails or faxes, make calls to a
number registered with the TPS, or make any automated
marketing calls under PECR. They will also need
consent to pass customer details on to another organisation
under the first data protection principle. If they cannot
demonstrate that they had valid consent, they may be subject
to enforcement action.'"

I see him at the Hive. Never had a number or Email for him.