It's not like they're sitting on piles of cash or other investments that are losing value. If costs go up they'll have to raise prices, just as the prices for what they're buying went up due to rising costs further upstream.
I figured the pandemic cleared out most of the small businesses that would have failed within five years anyway (half do). I wouldn't assume the small businesses left would have as much trouble with inflation as larger ones that operate at greater scales with tighter margins.