There're several reasons why it's advised to buy local art. First, it supports local community. When you buy local art, you not only support local economy because money go to the local budget, but you support local artists themselves financially and encourage them to create more. You also may get an opportunity to meet them personally, learn more about their work, creative process, and maybe even become friends with them or make some connections, that can be useful for you in the future. Buying local art also supports an ecology, because it reduces transportation and shipping lowering carbon emissions. Additionally to that, you most probably get a unique, carefully crafted with love piece of art, unlike mass-produced ones. And since they're local artists there's a high possibility to find something inspired by local sceneries, cultural heritage, events. etc. which may be easy to connect for you and helps to preserve the local cultural heritage itself.