I think that's interesting because most of my straight friends that do have friends with benefits are like that, it is only about the sex with them and there usually isn't much friendship involved. They also never really end up developing romantic feelings for their fwb because its a different kind of relationship than a romantic one. But I also think that is more acceptable socially for straight people to have those kinds of relationships because its only temporary. They will eventually settle down they just don't have time to go on dates until their careers are settled but they still want sex.
I also think that most alloromantic aces have it easier than both aroaces and aro allosexuals. That's the whole reason I hate AVEN, my aromanticism is much more important to my long term life and adult relationships than my asexuality. In a healthy relationship not having sex should not be the first thing about it, I know a heteroromantic asexual girl who got married and moved across state lines to be with the first straight man who told her that he didn't need to have sex. He ended up cheating on her and pressuring her into sex anyway. If someone is in a healthy celibate romantic relationship then most people won't actually know how much sex they are having. Any relationship in the media where they don't have sex and don't mention them having sex explicitly could be an asexual relationship because it's mostly normal.
Aromantic people, on the other hand, don't have the implied settling down later that's expected. We are seen as immature and told well want it later. It's more complex for aro allos because sex in the long term is socially connected to romance, especially after you reach a certain age. Casual sex and casual sexual partners are fine in college but people are demonized if they don't also have a romantic relationship to go along with it. Sex after college is often seen as a result of romance, where sex without romance is considered exploitative, and people who are not in romantic relationships pitied or infantilized.