A possible explanation, also from the ambergris Wikipedia page:
> Ambergris used to be very highly valued by perfumers as a fixative that allowed the scent to last much longer, but it has been replaced by synthetic ambroxan.
But buyers still exist for the natural stuff.
> A 1.1-kilogram (2.4 lb) lump of ambergris, found on a beach at Anglesey, Wales, was sold to a French buyer for £11,000 at an auction in Macclesfield, England, on 25 September 2015.
> Ambergris used to be very highly valued by perfumers as a fixative that allowed the scent to last much longer, but it has been replaced by synthetic ambroxan.
But buyers still exist for the natural stuff.
> A 1.1-kilogram (2.4 lb) lump of ambergris, found on a beach at Anglesey, Wales, was sold to a French buyer for £11,000 at an auction in Macclesfield, England, on 25 September 2015.