I've also read this several times. So I was wondering why are there so few nonstops from Buenos Aires?

As mentioned, many of them drive and others take charter flights (from December to March there were 300 charter flights operating EZE-FLN alone. This makes it more than 3 daily flights on the route!).

I've also read this several times. So I was wondering why are there so few nonstops from Buenos Aires?

Indeed, there are also regular flights on Sat/Sun by AR and TAM. In addition, GOL operates a daily flight.

Also consider that many fly to POA (which has 3 daily flights from EZE) and then take a 8h bus to FLN - this because many tourist dont stay in Floripa, but in one of the beaches along the coast from Florianopolis to POA/Porto Alegre.

Rgs,