Thank you everyone for your responses. I'm glad I asked first whether it was appropriate.
As for "hype," I think I'm right to be nervous because I've worked in Canada and I've worked in the US, friends of mine have also worked in both systems, and I'm able to make the comparison. The two sex industries are very different one from the other. It's dangerous there; and I know because they've come after me before (I've very narrowly escaped) and because of the ridiculous lengths that escorts have to go to to hide. I'd just as soon not do time in a foreign prison before I'm 21, and perhaps be unable to attend some professional conference in the US someday just because I charged for sex back in the '00s. If it were just fingerprinting, deportation and temporarily being banned from the country, I could accept that, but I just don't know whether it will be only that or prison too.
Furthermore, as Brandy said (thank you!) American escorts who live in the US have their own set of issues, but my particular concern is getting grilled by National Security every time I go there to supplement my income. I'm a "known escort" in the sense that a number of police departments have files on me because they're watching us online! I have had experiences that confirm this with absolute certainty.
Although it's ideal not to mention sex ever (that works for Americans who live in the US full-time), the fact is that I openly advertise it online for my service in Canada. That's just how the industry works here - because no one has to fear arrest, you have to talk about it openly to make any money. All the advertising and communication here deals with anal, oral, condoms, watersports, the works. I imagine it's similar in parts of Europe.
Because of this, I'd have to say to an American judge: "Why yes, I do actually prostitute myself in Canada, but in the US I sell nothing but innocent body rubs!" and have essentially no chance at all of being believed. This is why I wanted to confirm whether I had to be caught in the act, or whether it was possible to be arrested at the border just for being who they think I am.