.10/.20 blinds are a tad on the high side for a $10 buy-in (based on rates for online play). If I recall, $10 is typically the max buy-in for a .05/.10 table.
With most bets being that high, I'd definitely expect a higher buy-in to coincide. It's not far from the expected for the level of blinds you're playing at, but since the blinds are double what I'd expect for that buy-in, it only stands to reason...
- Jeffrey