I'm not sure about Canada, but in some countries, the congresses and other parliamentary bodies are frequently made up of people who were rich before going into politics. The other side of this coin is that all campaigning, etc are for the party and/or campaigning representative's account - and not a bill footed by the general electorate. In fact, a large proportion of the election process is funded through private funding almost entirely. Likewise, members of some congressional organisations in some governments are only paid very small amounts, and these amounts are only paid while representatives are actually in office. Once the official leaves office, they will likely pursue careers in a private sector so as to acquire more wealth, and as such will not be provided with a pension but will be paid out in accordance to their providend fund to which he or she subscribed while being in office.
Sometimes I wish we had a similar system here, but unfortunately it does open up the system for abuse, as we have clearly witnessed in the US in the last 2 presidential elections.