Over my range of tickets, I have numbers starting in the 13,000's up to 24,000's and my first lot were purchased first in line at Parramatta bout 9.02am - somehow I think the pax numbers are not the ticket count, as the NRL announced they have sold 12,000 tickets so far.
Incidentally, Doggies were BUL-***** (five numbers), though not sure why.
Another 'gap' with the system is if you go to an agency, they only take down your membership card number, so for Saints it's a 6 digit number (00xxxx) I had some roosters cards that were also numbers, but a 4 digit number (0000) it is fair to say that most clubs would also use a number system, and if the operator only put the 4 numbers in, ie: they don't include the first 2 zero's, then you could replicate the same range of numbers over several clubs.
They really don't think this sh*t out.