Sniffing is horrible!! Gives me the total rage. Just blow your nose!
I once had a team leader, who took and exercised her position of seniority veeeery seriously (much more so than any of the actual managers), who made my working day an absolute misery.
She would stage-whisper patronisingly to me to come over to her desk when the manager was away from his desk for 'advice' about all perceived peccadilloes, such as using my desk phone for outgoing calls rather than the payphone that nobody else in the whole place (including her) ever used. I'd done it for the first ever time, when I had to make a very urgent call in a panic to prevent a re-mortgage falling through because of an absurd false assumption by the lender. When I needed to make a follow-up call, I excused myself and said I was going to use the payphone and the manager spluttered incredulously "But why? There's a phone right there on your desk!!!"
She was one of these people who would randomly grill everybody she spoke to on the phone as to when they'd arrived, purely so that she could inform them that she'd already been there since 7:30 [actually more like 20 to 8] and scoff at those who didn't arrive until just before 9. What she never thought to mention, though, was that, after deliberately sending a one-word email when she arrived, to make the point, she would always spend the first hour and a quarter of every day fetching and eating a drawn-out breakfast (noisily) and on her desk phone, chatting with friends, arranging every dull aspect of her own personal life, before starting actual work at two minutes to nine - and then spending most of the day deflecting work by batting back requests and pulling people up because of the most ridiculously trivial typos and insignificant minor errors, before leaving at 'home time' - 4pm - and smugly telling those who did the standard core hours that had to be covered of 9-5 that they would have to stay 'late' because they 'hadn't got in until nine' (as was their normal agreed working pattern).
But enough ranting, rambling, digression and tenuous scene-setting: every single time I sniffed, even just once, she would call me over and ask if I wanted a tissue, so that I 'could' blow my nose.
She too bought into the common myth that every time a person sniffs, it can automatically be 'cured' if they simply blow their nose. People sniff for a whole range of health-related reasons - none of them 'just for fun' or 'to annoy you'. Her insistence that blowing my nose would instantly cure my (very quiet and occasional) sniffs, despite any explanations to the contrary, just made me paranoid and frightened to even breathe freely in her presence.
She wasn't an intentionally horrible person, but just extremely self-absorbed and self-important and certainly not one of life's thinkers. She would follow 'received wisdom' on everything and accept cliched sayings as proven, established fact (e.g. "There's no smoke without fire" and "People always die in threes"). She was of the school who would, genuinely thinking she was helping, frustrate and embarrass stammerers even more than they already felt by giving them the 'valuable pearls of advice' that they'd hitherto supposedly never ever heard from other ignorant blowhards such as "Breeeeaaathe," "Just slow dooooown" and "Now, think first what you actually want to say".
Far TL;DR: Believing and assuming that all sniffing can be instantly stopped by blowing your nose is very naive - and going as far as forcing a tissue on people and/or ordering them simply to stop (when you quite possibly have many far more annoying habits and behaviours yourself anyway) is both dim and arrogant in the extreme.