Most of them do. I was seeing 11.5 AFR hard on it with Revo 2+ (B9, T5, F8). That is ridiculous and totally defeats the purpose of DI. 12.8 is fine and makes more power, but most tuners chuck in loads of arse covering 'safe' fuelling.
Have you altered you Revo settings? IIRC, my originally supplied S1 settings were something like B6, T4, F9, and it covered my rear bumper with black soot. I progressively tweaked the settings to B9, T6, F8 for a summer map, and B6, T5, F7 for a winter map. No longer any black soot on the bumper, but the tailpipes are always sooty.
Systematic over-fuelling in any petrol car is a really bad idea, as it will strip oil from the bores, causing high wear, and is particularly bad in FSI motors.