This[0] from 2016 shows 13,500 outstanding cases of those "who skipped court bail while facing charges including murder, child sex offences and rape" in the UK.
It appears that Assange can be tried for "Bail, failure to surrender"[1][2]. (Maximum 3 months sentence unless sent for trial.) I'm not aware that he's be charged with anything else, so, on the face of it, the money could have been more usefully dispersed to protect the public.