Yes, you are right. It's a filter, not a crystal.
Perhaps for noise margins with lower VCC (2.2V to 3.6V for TRF vs. 5V for the TDA). Anyway, I am not going to worry about the physical size, except with the note: "smaller board can be made". The lower VCC is swinging me back into the TRF camp for now.
By the way, what would be good choices for RF Amps? It will be feeding directional antenna if output exceeds FCC limits.