No, but when i had Polish national visa they asked me to enter and exit from Poland territory.
When did this happen, and more importantly, who told you that?
As of 5 April 2010, holders of national visa (type D) are permitted to travel and stay in any Schengen country for up to 3 month within a half year period, provided some very basic conditions are met (valid travel document, financial means to support themselves, provable reason for travel, no red flag associated with the name within SIS and security agencies). This includes travel for the purpose of transit to and from destination state (in this case Poland).
In parallel, the same conditions apply if you have a valid residence permit. Remember that there are many destinations not connected to Poland via direct flights.
Speaking of red flag; have you travelled to Iraq, Jordan, Lebanon or Turkey recently?