Every advanced player that are really loves online poker with all his heart knows that the best strategy is always to test the field and bet on yourself. Betting is not the more expensive option, seeing as the last person to play would bet anyway. In fact, this adds value to the money. If the blind is betting, she normally has a strong hand, such as a pair or a set. If the last online casino player raises again, you could discover that they have a high pair and may then consider folding.
As such, had you just checked and allowed your opponent to bet, you would not have discovered this, but instead risked additional bets.