Seat height mounting bar retainers

[GrinningGSer]

Stopped after a long ride yesterday and when I dismounted I saw one of my seat bars protruding 15cm below my seat

I had not felt any undue seat movement

I removed the seat and found thet the foreward securing rubbers had perished and broken. The rear rubbers are perished, but have not broken yet
Dealer says that these are NOT a warrantable item

Two cost £3.10 incl vat and it looks like I need another two for the rear
(Front and rear are different)
Pic of perished, but not yet broken rear:

Is this a safety issue ?

 

[whitegloss]

Mine are also bust-thought i would get some new freebies but looks like i'll be stung for 3 pounds plus-what a crap design!!!!