Fair point Tony,
But:
1/ If your family member is travelling with you - then they already have your priority for upgrades.
2/ If your family member is special enough - you already gave them PG when you hit 2400, so they have SG priority in their own right when travelling without you.
3/ If you're already forking out upgrade points (eg. 72,000 for SYD-LAX Y to J upgrade), then instead of playing the lottery against the rest of us, fork out 96,000 for a confirmed classic award using your WP1 preferential access to open an award seat. And 500,000 points a year IMO is gazillion enough to spare the extra 24,000 if you really need to give a family member your priority (when they're not travelling with you and when you haven't already given them PG).
So in summary - more than enough reasons why a WP1 priority should NOT be extended to family and friends when travelling separate to the WP1 member.