So roughly in line with losing a third of one's annual income, or simply losing each month's wages, if looking at average salaries today

That's an awful lot to donate to a bunch of pixellated madness. Yet if BTG were to cease tomorrow, it matters not. With most players handing them a generous slice over the last couple of years and playing catch-up, their already laughing into the sunset.
As it stands, they're not in a hurry to do that mind. They'll just release another new slot and watch punters get themselves hyped anew