Qui-Gon is undercover and Anakin gives no indication of knowing or suspecting he is a Jedi at that moment in time.

To him he's just an off-worlder in search of a ship part and he would, I suppose assume that Jar-Jar is the same or maybe even his slave until Padme expresses how quaint the idea of slavery it to her.

Besides Anakin seems to have a one track mind (even at that age) he's only interested in Padme the angelic and barely notices Jar-Jar until he starts to wreck the shop.

He'd proberbly be more interested in R2 (I would be when I was his age).

I suppose George thought that Jar-Jar had to be in those scenes because if he wasn't Jar-Jar wouldn't be in those scenes (if you catch my drift).