You can profit from counting cards with a flat bet. The MIT team did exactly this. The trick is to have counters at multiple tables, all betting a small but flat amount, and floaters that move from table to table while betting large, but also flat, amounts.
The counters lose a small but steady amount of money over time while the floaters make large amounts of money by only playing at the tables with favourable counts.
The counters lose a small but steady amount of money over time while the floaters make large amounts of money by only playing at the tables with favourable counts.