There are hidden chance in this event. 
Most players think chance to have bad luck card from 2 cards is 50%. But real chance is 66%. Nexters make own chance for each level and in fact you will spend more, then you think you should.
I fixed description of my last video and make a new table. Here it is:

With the actual probabilities, the average number of cursed cards per full run is 6.64.

Therefore, the average cost for a complete run is:

25 – entry fee

25 – first mistake

50 – second mistake

75 – third mistake

100 – fourth mistake

125 – fifth mistake

150 – sixth mistake

150 × 0.64 – seventh mistake in 64 % of cases

Total: 646 Seer coins on average for one full run.

That comes to 4 500 for seven runs for 2 totems.

Add another 1 000 compared to the average cost with their original probabilities.