That elves don't get Arcane Marks even when they are mono wind users is the same reason that eventual High Magic users don't get them while they are learning each wind at the start of their life. Because they are able to spend years and even decades meditating on a spell and searching for errors before they first attempt it.
It is also a outcome of the different way that they practice magic that is enabled because their lifespan.
I agree that humans don't go out of their way to obtain arcane marks.
Elves are the same and infact they can go further to avoid getting marks. We know that getting Arcane Marks is a career killer for aspiring high mages. That tells us it is possible for them to get them and further more it explains a selection bias in High Magic users, and by extension Elven lords and the like.
Now as far as I can remember Elven mono wind users are either
A) Regular folks who just use basic magic to make their life easier and have no interest in further pursuit. We wouldn't know how frequently these people have Arcane marks because they do not feature prominently in the Lore.
B) Religious figures such as the Priests of Vaul who are generally pretty reclusive and see the use of a single wind as part of their worship. These people are probably somewhere between human wizard and elven culture, Arcane marks are a sign you fucked up in the past but not a career ender, however since they're not featured prominently in canon either its hard to gauge.
If someone can back this up or disprove it I'd appreciate it my memory is very spotty.
C) Future High Magic users who have to learn each wind individually. As noted previously these people are extremely arcane mark adverse and we can assume that any member who gets one swiftly finds a new career and exits this category presumably into A but also possibly B.
Its very hard to judge from this how common Arcane marks are from this however let me ask a question? How many famous mono wind elves can you think of? That'll let us know the sample size we're trying to pull from to establish how common arcane marks are.