The snowbirds typically end up in low cost, warm areas of the geographical area they live in. In the US, that means Florida for easterners and the dry deserts like Arizona for westerners for the most part. In Europe that means the Mediterranean areas like Sicily, Majorca, and Crete; and the French and Italian rivieras.
There is an entire industry built up that caters to retired folks. Retirement communities, for example, can be found all over the civilized world. These often have central show pieces like golf courses, swimming pools, and tennis courts that the retired folks can enjoy (usually for a fee). And such communities typically offer special events (for a fee) like going to baseball games, shopping at the local mall, enjoying movie night, and so on.
Been retired for 18 years now. But more than that, my mum in law lived in a retirement community and many of my friends currently live in them.