Chris Robinson got into it with fans at The Black Crowes' Florida concert ... beefing with folks who started chanting "U-S-A." Here's the deal ... the band was performing Sunday in Tampa as part of their "Southern Hospitality Tour" when a visual thrown on a screen reportedly showed the band's Black Crowe character dressed as Uncle Sam. A source tells TMZ ... before the band started playing "She Talks to Angels," the crowd started chanting "U.S.A." That's when Chris addressed the crowd, saying ..