I lost the will to live after reading a few posts in this thread, so skipped to the end. Apologies if this has been mentioned before...
The protocol in the RFU at semi-pro and pro levels is that if someone enters the playing area with a kicking tee after a penalty has been awarded, then that signals the intention of the team to kick at goal.
Teams know it, players know it and, in the main, it works and prevents issues where the match officials have then become the centre of a shit-storm that could have been avoided.
I think the consensus of the thread is that you'd be very jobsworth to apply that protocol at grass-roots level.
at grass roots level it seems sensible that
- if someone comes on with a tee, then his team loses the opportunity to go for a quick tap
- but the actions of a rogue tee-carrier can't, in fairness, commit a team to a kick at goal
- time off, send the tee carrier away, get everyone 10m back, time on