It appears to me that there may be several problems using this method, assuming it is workable.
1. You cannot play for high stakes.
Playing high level bets would bring such scrutiny that the special dice throwing would become evident or the casino may ask that you throw harder and bounce off the back wall ruining the method.
2. Would not be worth it for out of towners
In order for a trip to be worthwhile profitwise to Las Vegas you need to be a higher stakes player. I say this because the overhead of airfare, rooms, and a rental car eats up too much of the profits. Not being able to play for high stakes for an extended period makes comps improbable. Therefore it seems that only those without those overhead burdens (locals) could pursue this.
3. Very low hourly income.
Assuming that regular black chip action would very difficult to get away with coupled with the fact that crowded or even patially populated tables greatly limits the amount of throws an individual would get, makes the income level quite low. You cannot ask for a $100 game, as you can at 21, at the crap table. Assuming the dice thrower is betting green with a 2% advantage at the dice table and gets to shoot 5-10 times an hour, that barely amounts to much. This does not even include the smaller bets (losing bets) he may make when others not skilled shoot or the time wasted looking for another game.
Example: Assume a roulette player was playing double zero roulette betting green for 20 spins an hour. They house has a 5% advantage (far higher than the dice thrower). I mention this as this income is still low but still larger than the expert dice thrower with optimal (but not unrealistic) assumptions.
Roulette $25 X 20 spins X .05 = $25/hour (approximate)
Expert dice thrower: $100 X 10 throws X .02= $20/hour
(Optimal assumptions. More conservative numbers would yield far less income)
Such minimal play would never get you comped

