The thing with these type of contests is that you can become even the first if you want (and have the money for it) but does it really worth it? Will you be able to make money out of it? What is your purpose of joining into it and trying to achieve anything? Is it fun? Is it money? Is it the lower house edge due to contest prize? You have to know all of these before you join in.
For example, look at the winner, they gambled 5.16 bitcoins, 1% of that is 0.0516 bitcoins he made that back with the rewards of 0.0453, which means if you gambled just at the house edge levels without losing more than you could break even, yet the second one gambled 2.98 which has a 1% of 0.0298 yet he only got 0.024 which is not enough. It is all comes down to what you want and how lucky you are.
for gamblers the contests like these are not a source of income but a way to increase their chances to win , effectively decreasing the house edge
your math is correct, they didn't make any direct profit from the contest but they were playing with the house on almost equal terms , i.e. the House advantage was nullified because of the prize
so it all depends on how your sessions went , you could have made a decent profit + got the prize
if you plan to make money with it , I don't think it is possible on a regular basis since the variance will get you sooner or later
it takes you to lose your bank once and you will be in the red regardless of the prizes
some people do manage to wager 200x+ of their banks , with 4 btc equals 0.02 btc balance , if you are one of these geniuses , you can try and beat the system
Well, those people who wager that much with that small amount usually try to do some systems and that doesn't really change too much from the fact that people can't always win, no matter what your system is house edge eventually will get you. You can gamble with 0.02 btc balance and reach to 4 btc wagered but just because you can do it once, twice, thrice, doesn't matter how many times, doesn't mean that you will continue doing it forever, eventually you will end up losing. It is just simple as that.
I sincerely hope that people who wager on these contests only have one purpose which is dropping the house edge on their favor a bit, less than 1% thanks to rewards, if they have any other purpose to gamble for the contest like making money, they are dead wrong because it all depends on luck.
, you will get this Pop-up!
but it is a nice improvement, congratulations to that person. 
