Data suggests that an average project spent over $50,000 in listing fees to exchanges on the advisory list this year. This totals over $100 million stolen in 2018 via listing fees, with some exchanges making over $1 million from this alone.
From previous April 2019 Blockchain Transparancy Institute report:
During these months, we have also released over 200 full exchange reports to over 40 crypto projects enquiring about the legitimacy of the various exchanges contacting them for listing. The listing fee costs from just the wash trading exchanges in these reports totaled over 150 BTC. We are glad these reports were able to save some crypto projects from being scammed out of money that could be used for development instead.
Also see edit to my post above.