The choices we make can be moral, amoral, or immoral. Incentives aren't really relevant there.
For example, imagine you're walking out alone at night, and for some mysterious reason come across a little old lady on the street. She'll probably have a purse with her, and that's your incentive for robbing her.
But assuming you're not a psychopath, you won't even think of doing that. Even a psycho would be more likely to just mind his own business than rob her.
> the possession of money and property is a form of political power
Why would it be? Political authority is the perceived right to impose your will on others by force. Political power is the position to do that. Asking someone to do something in exchange for money is a potential trade.
There's nothing immoral about offering a woman $500k for a blowjob. She'll probably do it too. But it's her choice - she'll have to figure out if the $500k would be worth any loss of dignity she would experience as a result of selling you that blowjob. As long as it's voluntary, there's no problem. It's just a choice she'll make, and be responsible for.
> My ultimate point is that there are conflicts between the market economy and the democratic political structure.
I'm not sure what that means. But again, as long as there's political power, people with it will be bribed, regardless of what else happens in the economy. The solution is to abolish political power. You might note that coercion is immoral anyway, and perhaps start a line of questioning from that premise.