A foul tip signal in basketball can lead to trouble. If one official signals "foul tip" because he sees a clean block, and his partner comes in strong with a foul; you've got the equivalent of a double whistle blarge. Some officials may not care, but I'd much rather avoid explaining to a coach how I had a foul when my partner clearly signaled a clean block; and I'd rather avoid putting my partner into that position as well.
Furthermore, it's like back-pedaling; it tells coaches other officials that you're relatively new.
Honestly, in the leagues I've worked in; back pedaling and foul tip signals scream "amateur official" even louder than showing up in uniform.