Well, Jeebus on a frigging moped, what's the problem with frigging using profanity anyway when the situation calls for it? LOL.
It'd be an odds on bet that even the most devout of the Faithfools would utter a few profane words when either hammering in nail and hitting their finger/s instead or stubbing their toe on some piece of furniture.

The English armies that rampaged through France, during the Hundred Years War, would have thought themselves 'good Christians'. Yet, in addition to committing rape, pillage, mass murder, and arson,they "God damned" everything. They "God damned" French beer, French wine, French women, etc. So much so, that French soldiers began referring to them as "Goddamns" (which is supposedly the origin of the expression).

My late mum was a Christian, and she swore quite a lot

BullSHIT....bible is full of obscenities ....preachers can go fuck themselves for calling all Atheists "fools" and "reprobates"

No. Less so because there's so much less to swear about.
It is what it is, is my attitude.

Depends, the religious people have the same outbursts of emotion, they just use different kinds of expressions to communicate it.
F* you
Bugger you.
Frack you
God have mercy of you
God loves you

All those expressions can express the same "go away" intent, the non profane version are just workarounds to not use the direct expression
But yes, I think we non believers have one less thing that suppress the direct language.
But of course children or even trying to de-escalate the speech can make us not use direct expressions.

I for instance live in a country where I need to use a second or even third language, and I swear a lot less than in my primary language.

WHAT?

no they are not

I see no reason to expect it.

The most vulgar and biggest users of various substances I know are highly religious.

I do most of my swearing on stand up Comedy. It's so awesome to swear and be all and end all.

I swear more on this site than I do with my family. Then swear even less again in Public because I like for people to like me.

Sh#t, that's a good fuc#ing question. Actually, I don't swear any more as a non-believer than I did as a believer. I just don't think a god is watching and giving a rat's as#.

Btw..I don't really swear that much; but when the occasion calls for it, I don't shy away from using certain flowery words (depending on the company I am in, of course).

However, I am a non-believer who does not like, and does not want to watch, porn.

I use closed captions playing movies and often note substituted words replacing true epithets easily lip read by the cast.....James Earl Jones SAID SHIT but censors typed SHOOT.....nobody says shoot frustrated for a single word FIELD OF DREAMS IOWA movie gets a G RATING

My youngest daughter and I both swear like sailors. We could be bad influences on each other as we both work with the public which is likely why we swear in the first place.

I dont. Actually Ive found a general trend that younger folks are morecomfy woth casual profanity. And younger folks also tend to be nonreligious....so....yeah.