Depends. The simple yes/no won't make justice to the question.

My personal guidelines:

(1) If there's a FOSS alternative, use that.
(2) If the copy is for educational purposes (non-profit, not for keeping), it's ok to try it before spending disproportional amount of my income.
(3) If I have the money, buy it.
(4) If I'm making money with it, buy it.

Disclaimer: I'm not encouraging anyone to pirate software.

For several years now, most of the stuff has been covered by (1) for me.