Snaer, a senior guard who sat out a win over Louisiana-Monroe on Monday for disciplinary reasons, had 17 points at halftime and hit two free throws with 11.8 seconds remaining to help seal the win.
Thomas, a freshman guard, came off the bench and scored 15 of his points in the second half and hit one of two free throws with 3.4 seconds left to give the Seminoles (7-4) their final margin.
The Seminoles trailed 40-35 at halftime but went on a 10-0 spurt early in the second half and took the lead for good at 47-45. They went on to lead by as many as nine points and held off several surges by Charlotte (11-2) down the stretch.
Both Charlotte's losses have come to Atlantic Coast Conference teams. The 49ers lost 77-46 at Miami on Dec. 14.
Chris Braswell led Charlotte with 20 points and Mayfield scored 16.