In tournaments, one wants to avoid busting. And one can use that fact against others -- will the opponent risk his tourney life on this hand? How much of a bet is needed to raise that concern in others? Does that bet put you at considerable risk? Is the risk worth it, this time?
This life-and-death evaluation is not a factor at cash tables. People make a choice whether to risk their stacks -- but if they lose the hand, they can buy another stack. It changes things.
The other difference is that, aside from the cashout tourneys, one has to stay alive in a tourney for quite awhile to make money. You have no choice where you sit, nor who you play against. You have to survive no matter what the table is like, what the other players are like.
At a cash table, you have choices. You are not tied to that table, nor do you have to play for a set period of time. And the other players can stay or leave also At a cash table, a player can sit down, make some money and leave. Or lose a hand badly and leave. Or change tables because they want a different balance of players. Some people pay a lot of attention to who the other players are, and choose tables accordingly. . If you are regularly beating up on a fella, he can just leave. This, too, changes things.