With support like that, who knows? It's not inherently sillier than an independent Scotland or an independent Catalonia anyway - or an independent Luxembourg, come to think of it.
Of course Italy was split into multiple nations until 150 years ago, but I would say the difference is that Catalonia and Scotland have particular identities clearly distinct from the whole bloc of their countries. Veneto might have strong peculiarities, but no more than, say, Apulia, Emilia or Campania. Italy is a construct of multiple regional identities, which is very different from relatively homogeneous blocs like UK and Spain where one or two specific regions clearly stand out.
The Rest of Spain (say, without Catalonia and the Basque Country) is not a homogeneous bloc but a "construct of multiple regional identities". There are a lot of geographical and historical circumstances that makes Spain more diverse than England. Anyways Veneto is not Scotland nor Catalonia.
