Feet Don't Fail Me Now  Shoe manufacturer must differentiate its
offerings from cheaper imitators through marketing and
advertising.   Feet Don't Fail Me Now    It took 20 years for
Margot Fraser to turn Birkenstock sandals from hippie
affectations into industry leaders. Now she's discovered, as
every niche exploiter eventually does, that nothing breeds
competition like success. Can her company survive the attack?
In the beginning Birkenstock shoes were the brogan kin to the
ugly duckling -- paddle-shaped Jesus sandals perceived as so
pathetically homely that their main market was health-food-store
owners. They'd wear them behind makeshift counters, feet propped
up on bulk bins of wheat bran and organically grown nuts. The
sandals were plain, but they were comfortable, and there was
nothing else like them on the market.  Margot Fraser of Santa
Cruz, Calif., had chanced upon Birkenstocks in 1966 while
visiting her native Germany. The sandals were a new product of
Birkenstock Orthopadie GmbH, in Bad Honnef. Th