Obvious bait, but some add-ons/plugins are not for 'cheating', but rather for accessibility. Some aspects of the game are difficult to see or process mid-battle (like the colour difference between your own DoTs/debuffs and someone else's), and using something to help you see better doesn't mean you're cheating.

People can use add-ons to cheat, but not all add-ons are cheats. Know the difference.