Some Druid Drip (Patreon)

Druid always come prepared to greet his Alchemist friend at the train station whenever he visits Mother Tree. Alchem comes to visit to do work on his special potion project with Druid. Since his project has limited materials back at his hometown. Mother Tree is a place full of herbs and other materials he needs. Though his acess is limited without Druid's help. 

On the other hand, the project's not the only reason.