Doubtful that there is a specific hack, but...
If you have a child from your household on the lot (either bring the kid along with a teen or adult when visiting the lot or teleport a child in and use a temporary, reversible change to make him/her a non-visitor), AND if it is daytime, AND if it is not school hours or is a weekend day, then you should more regularly get some other kids showing up on the lot.
Adults visiting the lot make the game spawn more adult visitors; teens visiting spawn a greater percentage of other visiting teens than just adult visitors do; kids will help to spawn a greater than the norm but still small percentage of kid visitors.
EDIT: Should add that I just don't know whether or not child visitors can actually purchase items. Depends on whether the game's animations include specific activities (such as holding the shopping bag, handiing the cashier payment) geared for children.
Hmm ok.. I think it reflects on the thing where children can't call for a taxi from thier homes so it would make sence not being able to come to lots if that was the reason..
And yes Rarely on occassions i have seen Child visitors purchase from shops but this is only if the OFB is active and your lowering the price of the items to about 1 simolion.. so basicaly its something to do with children not having the money to do it.. and possibly on Rich children can..
