There is a subtle effect in the taxation system within a democracy that minority groups or special interest groups can get a disproportionate share of government subsidies.
This is basically because of hidden taxes, and hidden subsidies. People see how much income tax and goods and services tax (GST) they pay, but generally don't see how much other tax they pay. Excises on fuel, wholesale sales tax, land taxes, re-zoning land taxes and so on people don't get to see. Hence they don't know how much income they are missing out on via subsidization. However people generally are aware (though quick to deny) the level of subsidization they get. People may be aware of the basic unemployment rate, for example, but few are aware of all the smaller subsidies in the form of child welfare payments, rental assistance, hardship allowances and so on.
Hence, it is possible for a politician, or political party to buy votes by silently taxing the majority, and giving subsidies so special interest groups. The majority are unlikely to change their vote because of a small tax-slug (particularly if they are unaware of it), but the minority group are very likely to change their vote to get the extra payments.
This works wherever it is possible to hide or disguise the payments taken from the tax payers, and the payments made to special interest groups.
More generally, special interest groups can effect policy by making demands which can be hidden from the majority. No person can completely assess the impact of every government decision. Making decisions which a small number of people are likely to change their vote over, but which the rest of the population will never even be aware of are good policies for re-election.
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