The reason I was thinking that because the way the staff at counters play games and mind games, it seems whatever fee they charge extra, goes into their own pockets or a hefty share of that is given to them...Why wouldn't he know? There is every reason to suspect that employees at BLS are doing this at the behest (and likely coerced) by their upper management. Every application re-filled using their value added services brings in $$. Its hard to think even the most sadistic employee would enjoy refilling 70 to 80% of applications for manufactured "mistakes", working non-stop from 8 am to 4:30pm for a low pay --- which is all what at least 3 "VAC" counters at Toronto office do these days. I believe fleecing applicants through predatory practices is the business MO of BLS management.
Every single application I have submitted at BLS counters in last 10+ years have been accepted only because me forcing them (standing one's ground as you say) and ignoring their final threat that this will be rejected by CGI punctuated by "no refund"! Nothing has ever been rejected by CGI in my case.
That said, this is not going to change until HCI stops accepting unreasonably low bids by agencies like BLS tailored to force out competition. The actual revenue strategy being fleecing gullible applicants, fees matter little to them. $7 to $9 of service fee per application is too low to be sustainable for any honest operation.
But your points make more sense that they will not dare something like that without management approval.