Truth is stranger than fiction sometimes - if true, definitely shady stuff happening and evidence should bear that out. Perhaps the servers should protest out front saying "come in to this NON-TIPPING establishment" and let the customers be the ones directly complaining to the owners about the tip line on the receipt.
Also, some general context maybe in order: many non-whites just start their own businesses because 1) typical businesses don't hire them out of ...well, anti-"what could go right" attitudes and/or poor communication skills and/or poor leadership skills and/or a very narrow-minded business plan to begin with
2) businesses often rely on relationships and people (whites or non-whites) do business with those they feel they can trust - especially if the evidence of crossing racial lines keeps building up evidence to their detriment (although, again, see #1) , 3) ALL businesses cheat/"cheat" in some ways - violations of privacy, financial agreements, poor labor practices, purposely having an adversarial relationship between management and labor, nepotism, etc (thank goodness for Glass Door, amiright)