PSN still charges me taxes last time I tried for sure.
I think it makes sense to charge taxes on PS+ cards since...well...you're buying something.
What really sucks is paying taxes on point cards since PSN will still charge you taxes on your PSN purchases so you basically pay taxes twice. That's a fucking ripoff.
What? Really? I've never been taxed on anything involving PSN. Not the PS+ memberships, not the wallet cards and definitely not the games.