For most tourist boards/tourism agencies/DMOs etc the membership subscriptions they receive from members are just a small part of their total budget. They receive more from corporates, from local authorities, from govt funding. They need to show they're "engaging" with smaller businesses in order to get some of the bigger funding but your membership subscription is a small proportion of the total.
Bear in mind that in most cases you're paying into a central promotional pot that works for the common good, to promote the whole area rather than individual businesses or smaller areas. If it's important to you to really feel you're being promoted more directly, you'll be better offer getting together a small group of local businesses and paying some one to do some more intensive promotion on your behalf (I'm often asked to do this and sometimes it's the best option but sometimes it's a good idea to pay into a central tourist board pot).
What are the membership benefits on offer? Which are really relevant to you? Do they sound value for money? If you're already a member and thinking about re-joining, what value did you get in the previous year?
Don't re-join if you're simply scared of not being a member (almost certainly nothing will happen) - re-join for positive reasons.
Do they listen? Are staff interested in your business and your area? Does their website and promotional activity demonstrate this? Do they willingly link and promote local area websites as well as their own, or are they mainly interested in their own self-promotion?
Are their marketing themes relevant to you? Do they give advance notice of their marketing activity so you can piggy back on it? Just as importantly do they feedback with meaningful information on what they've done?
If you do join up/remain a member, you will probably be asked to fill in a form describing your services, in a set number of words. Make sure you do so, carefully considering the words you use. This short description is likely to be used in many different ways, going to a wide audience so make sure you stress your unique selling point and key benefits. Make it count!
Remember, your tourist board has many members all competing for attention. You must make sure you are as prominent as possible. The members who shout loudest are most likely to be heard.
If you don't think you are getting value for money, don't just let your membership lapse. Speak to your tourist board and suggest the kind of services you need. As membership organisations, feedback should be important to them.