SL-Mark: 
"Being beaten in a dice game, well it was simply that the die favoured the other player! i.e. luck."
"Beaten in a game of skill, however, then the loser can only critique themselves."

Those observations are a good start.

Being beaten in a dice game, one can all too easily conclude that the loss was purely a matter of bad luck, and that there was nothing in one's own play that deserved criticism.
Not all dice games are created equal.
Have you ever noticed that the frequency of claims of "unfair dice" tends to be inversely proportional to players' strength?

"Dice games require less thinking?"
Who would say such a thing?  On the contrary (at least in some dice games), in addition to strategic considerations, one must also calculate various probabilities.