Am I right in thinking that those claiming Jobseeker's Allowance have to prove they have made x number of job applications each week? If so then that might account for such a large number.
As a recruiter I think it is very short sighted to only accept the first 30, how can they be sure the right person has seen the job. I might only look at the 30 who had the right experience and bin the others though. Surely a closing date is given and would give people time to think about their application rather than sending it off in a rush in order to be in the 30.
I used to first read the accompanying letter/email and see if it related to the job advertised or was just the applicant's standard letter. That didn't take long and usually weeded out the dross.
If they are repeatedly advertising the same job their recruitment policy is wrong. If they can't keep the person in post, again, their recruitment is at fault. It takes a minimum 3 months to get someone doing even the simplest job at a passable level which is wasted if they leave. Not enough attention is paid to good recruitment imo, should be done with the assistance of someone who knows how to do it.