The law in Maryland was introduced to promote the use of local ingredients and farming in general. This used to be a big farm area before the suburban sprawl and Washington money, and anything that encourages the growth of industries that use Maryland agriculture is seen as a positive. The current thinking is that local food is good for your health, your taste buds, and the environment. You pay less for the license but otherwise will have to meet the same requirements as any other licensee. An advantage here is that you can sell for on-premise consumption from 10am-6pm without a separate class D liquor license. However, you can only serve your own beer and the restriction that you grow one of the main ingredients for the beer more than offsets the benefits if you're just looking for a loophole / easy way to get into the business.