Sometimes saying it hits a ton is just sales talk trying to hype the cue up.
Other times they can be serious, but maybe someone told them another cue hits a ton and a half and they feel they need to sell the cue that only hits a ton and get the new one that hits a ton and a half.
Other times the guy just flips cues and hopes to make a profit and knows the cue hits great. Sometimes people get in a slump and another cue helps them feel a little better at the table so they want a change. Sometimes people change cues without knowing the reason they can no longer get the action they once got is because their tip is needing replaced. They know the cue used to play just like they wanted and was awesome, but now want something a little different, when what they really need is a new tip.
Also when you pick up a new cue and it allows you to pocket balls a little easier than your existing cue you instantly feel that advantage and buy it. After a little while you might notice you can't move the cue ball around as easily. So you pick up another cue and it has a lot of action. So you change. Then after a little while you notice you are missing more balls and pick up another cue that pockets balls a little easier or feels a little different in a good way and the cycle goes on. Everyone of those cues "Hit a ton" when comparing one or two aspects, but no cue does it all the best. So everyone is searching for that happy medium that suits them the best. If we want something that is super strong on every type of shot we would need a golf bag full of cues that were tuned for different aspects of the game.
