Read the full letter, gonna be blunt. While a few potentially legit employment law grievances toward the end, the language up front borders on obnoxious. I can't speak to the racial make-up of the back of the house, but I've never personally seen an African-American in the front of the house. It's incredibly tone deaf for primarily white employees to compare themselves TO SLAVES because they had to show up to a 9 a.m. meeting that should've been an email and have to shake the cold brew 10 times.
They have a point about the tips -- you can't pay a tip wage then tell them not to accept tips, should be paying at least minimum wage -- and I can't speak to the ADA issue, tho I doubt the Mouse would've let them build a noncompliant shop. But overall come off as petulant, overly dramatic children.