A couple quick thoughts:
1) When you have good hands, you need to get your chips in the pot. While your wins won't always be based on just your cards, if you're folding when you have a good chance to win, you're just making winning a tournament that much harder.
2) If you start playing really timid against a table of people who are paying attention, expect to start seeing bigger bets becoming more common and fewer calls when you're trying to extract chips from your opponents. If this is part of your long-term strategy (ie setting up later slow-play and bluffs) then that's fine, but if you can't 'switch gears' then you might find yourself folding with the best hand far too often
3) The bad beats may not be coming as often as you think. It's easy to remember when you get rivered and knocked out of a tournament, but you don't always count the number of times that your set or top pair hold up during the tournanment, so there is often some selective memory about luck. Unless you believe that someone (the dealer, the poker room, the gods of fortune, karma, the random number generator) is out to get you, you are probably winning a reasonable number of times.
All in all, if you can't let a few lucky draws make you change your betting habits. If you prefer to play tight, then play tight, but if you have a probably winning hand, then (depending on some other factors) you probably need to bet.