You're right, they shouldn't be mixed and SYRIZA is not really anti-EU. But UKIP and LePen are anti-EU while Podemos and SYRIZA will probably not comply with Brussels.
All of them may be oppose to the EU (or EU's austerity policy) for different reason, however the fact that all these new parties are a product of the EU's choice of policy remains IMHO.
UKIP is mainly a product of the Labour party policy rather than EU policy. Upon the expansion of the EU in 2004, the Blair government did not put any restrictions on freedom of movement[1] unlike Germany, France, Netherlands, etc. Predictably, the UK was drowned in a torrent of migrants.
UKIP is a nationalist party: they don't just want to be removed from the EU, but the EEA and the Council of Europe too.
All of them may be oppose to the EU (or EU's austerity policy) for different reason, however the fact that all these new parties are a product of the EU's choice of policy remains IMHO.