Is the theory of Probability really practical? This may sound naive but consider this, when we toss a die we impose a lot of restrictions on it like the die is fair, the outcomes are equally likely( in a sense they are ) and neglect other factors that affect it, then are we studying the outcomes in some sort of an imaginary plane beyond the external world? Why don’t we consider factors like the speed in which a die is rolled or the surface on which it is rolled and so on? Of course it could get too complicated but if we remove the real external effects what are trying to measure? And for example the coin tossing experiment done by J.E.Kerrich gives a substantial value for the empirical definition of probability but in his 10 sets of 1000 tosses there IS a possibility that every single outcome could have been a tail isn’t it? I don’t know if I have properly put down my question but there is some sort of an uneasiness that I feel with regard to probability.

Dice are used for random drawings because their outcome is unpredictable. Indeed, the laws of their trajectory correspond to a chaotic system, which exponentially magnifies the uncertainty on the initial conditions. To such an extent that quantum effects probably start to play a significant role.
In any case, when we throw dice, we don't have the information about these initial conditions.
This said, all dice are probably biased, just by the fact that they don't read the same number of dots on all faces, and instead of a probability $0.166666666666$ of getting a one, truth could be $0.1666665531$ (even varying over time).
Now the probability of $1000$ successive ones is like $7.0 \times10^{-779}$ and I can bet you will not see it in your lifetime. Nor anybody in the whole known Universe for the next millennium.

To answer the question in the title, yes the theory of probability is indisputably extremely practical and usually we have more than enough with two-significant-digits answers.
To further substantiate my claim, consider the developments of statistical physics, which is able to describe with excellent accuracy the behavior of gases, which are made of billion billion molecules, even though we don't have the faintest idea of the positions and speeds of any of them.
