Not necessarily. Squats and deads help develop your abs and back stablizer muscles. If you wear a belt all the time, these muscles won't develop as well. I think belts should only be worn on your heaviest sets.
That is exactly why you would not want to wear a belt. The belt is a crutch and it will slow the growth of your back and AB muscles relative to the rest of your body. Perfect your form and you will not need a belt. Reduce your weight for a while if you have to, just to get used to not having a belt, but do not use a belt just to save your back, you are not really doing so. Gaining strength in your back and ABs is what will prevent future back problems.
You should only use a belt when lifting over about 85% of max. You need a strong back to squat, so you should not use a belt unless you are lifting heavy.
working w/o a belt will make your lower back grow stronger
yeh i never used to use a belt intill i found myself with a hernia i had to go for surgery then sit around in bed for like 2 weeks straight therefore i lost like 20 lbs cuz even after i couldnt lift for a while so it is a good idea to just use a belt regardless i know i do now