The short answer is that there are other nearby communities that offer more properties which are more suitable for vacation use than Lillian. Snowbirds seem to congregate heavily in the Gulf Shores and Orange Beach areas of Baldwin County, due to the attractiveness of the gulf beaches and numerous businesses that provide services for vacationers.
However, I know that some snowbirds do prefer to stay in other waterfront communities, like Lillian and Fairhope, so there is always the potential for renting a propoerty in Lillian to snowbirds.
One of the biggest decisions you have to make in a rental investment is whether to rent short-term or long-term. Keep in mind that if you plan to rent to snowbirds, then you will forgo the opportunity to lease your property for 12 months or more to a long-term renter. This will work well if you plan to make personal use of the property when unoccupied by renters, or if you plan to rent by the week during the summer, and you have a property that is attractive for vacation use.
If the property you purchase is not on or near the water, you might consider long-term rental, since there is a healthy demand for nice rental properties in south Baldwin County.