Ha ha ha.

You're right. It's not worth trying to bluff weak players, especially in low limit. The weak player cannot respect the cards you might have, he only sees his bottom or second bottom pair and thinks he is winning. So he calls.

Make your hand and let him make the mistake of calling. You will get paid off. With top pair, you have an excellent chance of getting the call, even with a medium or poor kicker, if your opponent is weak.