the best i've seen so far is..
"pretty to see, nice to touch. Once broken, considered sold".
Actually its not really unfriendly. most people accept that if u
break other people stuff u have to pay.. just that theres a small
minority of stingy people who would probably refuse to pay after
breaking without that clause.. so store keepers with fragile stuff
will want to put that sign there lo.. 1 is to remind people to be
careful , 2 is to ensure that when things are broken people will
pay up