Way too much. My sons play as well, and just like fortnite they couldn't save their battlepass tokens. While their chore money bought their additional battle passes technically I had to pay for seasons 1-3.
For myself personally most of my entertainment money was used on Apex until mid season 2, where the lag and code leaf forced me to decide not to put any more money into this game.
I would hate to guess as to the sum total of money, but I m going to assume that I am a "whale", since I have every legendary skin for Wraith, Pathfinder, Lifeline, Octane, mirage and am missing 1 for Caustic, Bloodhound, and Bangalore. I also have the Kunaii for wraith, which is funny since i don't really play as her.
All in all I look at as money well spent, I for the most part still enjoy the game and will support it as long as I can enjoy playing it. Couldn't resist the wraith witch costume either so got that one. I am thinking I should main her but I am having too much fun with Crypto this season to even consider it.