Pretty sure a band like Anthrax has a guaranteed rate for each show and if tickets aren’t moving than that effects the promoters bottom line. What likely happened is between the contracts were signed for a set appearance fee, costs for moving the band between shows went up enough so the band would break even or lose money.
One UK label head off the top of his head said that between the costs of visas, airfare, Lawyers, etc A band of four from the UK will have already spent 10k upon arriving for a tour.
David Lowery over the weekend posted a spreadsheet sheet for Cracker’s touring revenue from the 90s, when they were in demand, if you want a glimpse at the finances of a tour. I’m sure it ruffled some promoters feathers…