sounds like age discrimination to me

I think the W.A. regulations regarding bikes on footpaths are pretty similar to those you just showed us- but the prevailing attitude that I have come across with police is that as long as the bike riders act responsibly around pedestrians they will be left alone.
Mugs like me that just trundle down to the shops at a sedate pace, (about the best I can do)

while giving foot traffic plenty of warning and room tend to be left alone.
Lycrayob with head down/tail up busting his neck to go as fast as possible, and with restricted vision causing problems for granny on her gopher, or yummy mummy with the pram will get jumped on pretty hard by Mr Plod. Then Lycrayob has the gall to complain about road traffic being too dangerous for him so he needs the footpath!
Stephen.