How do recruiters go through online applications?

 Recruiter ask you to fill in online application forms to have comparible data of multiple candidates and to store not immediately fitting candidates in their application tracking system for future reference and follow up interviews.

So pre-sorting is normally done either directly by the ATS system or by recruiting assistants who are following basic selection criteria. Not filling out application forms will rule you out even before somebody takes a serious look at your resume.

Why should a recruiter invest their time into you when you do not invest your time into them?

I personally will rule out any candidate who shows already a lazy attitude in filling out a simple form. What shall I except later on at work. The assumption is most likely them same unprofessional attitude.