Academic CV's, on the other hand, usually list every scholarly publication their author has made, every academic honour received and so on. They can be as long as they need to be to list everything.
I think we may be talking about different things here. A recent ad for an Oxbridge lectureship required applicants to submit:
1. full contact details;
2. covering letter/statement stating how they meet crieria set out in the job spec;
3. a full CV
and (my emphasis -5jj) publications list;
4. names and contact details of three referees.
The whole package, particularly for a senior post at a leading university may well run to a couple of dozen or more pages, but the CV itself will not.
A British CV is just a record of your education and jobs.
Your education part prior to the age of 18 takes one line, the first degree perhaps two lines. Even post-bachelor degrees will not take up a great deal of space - important, relevant research work and posts of responsibility will be highlighted in the covering letter.
Details of your career will cover every job you had since graduation (though not part-time vacation work unless directly relevant to the job applied for. Few details will be given of jobs held more than five years ago unless directly relevant.
Very little space will be devoted to hobbies unless, once again, directly relevant.
The employer wants to know from a CV whether applicants have the right qualifications, experience and career path for the job - that's all. They will be quite interested in your current post, because that has a direct bearing on what you can bring to the post they want to fill. That's why a British CV, even for an academic post, tends to be short.
The future employers will initially glance through the CV, have a quick look over the names of the journals you have published in (are they respected in the relevant field(s)?), and possibly glance at the names of the referees (if you are applying for a senior post at a Russell Group university your old headteacher and a junior lecturer at a former polytechnic will not impress). At this stage, s/he will not wish to wade through thirty or forty pages to hunt out the vital information.