Is there any gambling project that have a soccer game and horse racing game onboard? I believe that these two genre are not based on luck but skill that's why I ask this question, since most gambling projects have games that are based on luck like roulette and others.
Well, in my opinion, i think one still need luck even in games that require skill to win, like in soccer and horse racing that you mentioned, the skill required is knowledge, the gambler have to know some vital stuff about the teams and how they play to be able to predict the out come of a match correctly, also i think knowing how a different teams perform under different weather conditions is also a vital asset as knowledge to have in sports betting.
But even with all this knowledge, you have need some atom of luck to win since knowledge is never enough, because after doing your best in betting with your knowledge, some things can change in the pitch that will utter the result of the game and your prediction.
So personally, i think the role of luck is still very much needed even in skill/knowledge based games/gambling.