That's part of the design of the game.Sarah Kerrigan said:Because some trap cards alot of people use are horribly overpowered. I've never been a fan of that and thats why I lost alot of tournaments.
Its always people with no strong monsters or spells and then WHAM kills me with one powerful trap cards. It drives me crazy
There are upsides and downsides to using trap cards like that.
Upsides are, as has been mentioned, they can be really powerful.
Downsides?
A skilled opponent can evade them.
Often, the powerful ones have specific activation conditions.
Mirror Force and Torrential Tribute for example are some of the strongest around, but they still have conditions needed to trigger them.
Choose not to use them, your decision.
But, yeah.
Not cheating.
Also, you may benefit from reading this page.
http://www.sirlin.net/ptw-book/intermediates-guide.html