Well, in the case of the US the voter has consistently and demonstrably voted against their own interests for a while now. How else would you explain e.g. the flood of money from the middle classes to the rich since at least Reagan, the corporatism (as opposed to just "capitalism") we now toil under, etc.
I often hear lower middle class people suggesting it is more important for the mega corporate monopoly they work for to get big tax breaks, etc., than for they themselves! I think these people always want breaks for the rich because they envision being rich some day themselves. Ironically the very policies they are in favor of appear to actually be preventing them from prosperity.
They are not voting against their interests. If you can even say that voting in a 2 party system allows one to vote for their "interests", in general it's voting for the lesser of 2 evils.
Income disparity is not in and of itself a bad thing. Corporatism and Statism is philosophy both major parties, so unless you vote 3rd party (libertarian for me) then you're voting for corporatism.
"I often hear lower middle class people suggesting it is more important for the mega corporate monopoly they work for to get big tax breaks, etc., than for they themselves!" Perhaps they're taking a principled stand that:
1. Corporations and small business pay too much in taxes.
2. Rich people pay more than their fair share in taxes.
3. They recognize that having a low tax environment encourages long term prosperity and are thinking the long term instead of the short term to see how much they can get.
The philosophy you are espousing is that middle class voters (the majority) should vote for themselves to not pay taxes and for the rich to pay all taxes since that would be their best interests.
An astonishing 43.4 percent of Americans now pay zero or negative federal income taxes. The number of single or jointly-filing "taxpayers" - the word must be applied sparingly - who pay no taxes or receive government handouts has reached 65.6 million, out of a total of 151 million.
I often hear lower middle class people suggesting it is more important for the mega corporate monopoly they work for to get big tax breaks, etc., than for they themselves! I think these people always want breaks for the rich because they envision being rich some day themselves. Ironically the very policies they are in favor of appear to actually be preventing them from prosperity.