I'd imagine most are angry for the same reasons as the rest of us are i.e., because our quality of living is diminishing and inequality is worsening.
The problem is those on the right refuse to hold those responsible for this to account and instead look to punch down.
Immigration is the perfect example. They often claim they're worried about the impact of mass migration on public services and infrastructure, which is a fair concern. But what do they do to address it? That's right, they elect a party who's entite political philosophy supports mass migration. The same party who have overseen a 250% increase in net migration since they took office, decimated public services and refused to invest in infrastructure.
And who do they blame for this? The people in power who made the decisions? Of course not. The people who keep believing the lies and spin? Don't be daft. No, it's the fault of the 45000 or so asylum seekers and the 'looney left'.
But let's not pretend that the people on those marches yesterday care about any of the things aboce. For them it's all about race and 'culture'.
If you asked them whether they're bothered about a white person from Melbourne or Kansas moving to Manchester or Kent they wouldn't give a shit. Their objection is purely focused on brown people. That's why they're so bothered about the 45,000 or so 'boat people' while ignoring the 1,200,000 legal migrants the tories gave leave to last year.